the thing is you don't have the car yet.
it really has to be in front of you, in your hands to see how bad things are.
in this situation i would want to thoroughly inspect this car from stem to stern.
then you need to figure out what you want this car to be. It tell you flat out for a regular 71 car based on what i see in the pictures you are already under water as far as cost to sell ratio.
if you want this car to be original some things will cost more and somethings will cost less.
the engine will cost more because you may need a total rebuild remember the car is 39 years old if that engine is original and has not been used in more then a few years and depending on storage it might be gone from the get go.
i had an engine that was crappily rebuilt sometime in 2000 .30 over then sat around for what seemed like 5 years, and had major rust pitting in the cylinder walls with the type of damage you would find if the engine heads were left off the motor and rain water was allowed to get in. i get it, it runs real bad and have to dump 5K for another rebuild just 6 years later according to receipts i found and if the Original owner is to be believed just 6000 miles later(i believe that was a big lie).
you need to get a lot more info out of the person you got it from.
how long did they own it?
when was it last on the road?
why did it stop being driven?
how long ago was it last started?
general maintenance?
was it stored outside or inside?
I see a picture of a car with no air cleaner base on it, anything from rain water to mice could of gotten inside and remember depending on where the engine stoped on its rotation any number of valves can be in the open position allowing rain water right into the engine where it could of frozen in the winter and busted the block internally.
that is why i say really think about what you want the car to be, in the end if you want the car to be a mach 1 clone then stop now, and get a mach 1 instead to start, because just having the 05 in the Vin bumps the valve up on resale at least 10K. then from there is different levels of mach 1 trim that again bump the value up.
if you want an upgraded suspension over ford stock, then your going to have the disadvantage of not having a staggered rear shock and sway bar setup, i'm in this boat when i got into my car i didn't even know about the competition suspension i assumed they all had it, and didn't even know about the fold down rear seats.
if you stick with stock mechanical bolt on parts then the parts are cheap, suspension will cost you about 1000$ for a total rebuild, if you go after market you could easily throw 5000$ into the suspension and then have all kind of issues to solve, like camber and ackerman angles.
if you have a standard interior in good shape then sticking with it and making repairs will be cheaper then swaping out parts and finding all the brackets you may be missing.
example my car had a deluxe interior, it was originally Vermillion(red) colored. somebody had gone inside and spray bombed it black, i literally mean somebody went into the car with a spray can of black paint and just started spraying over the interior seats and all to make it black colored. not only that but parts were missing, parts had disintegrated because of the sun, and age and abuse, and then everything was covered in black mold because the interior was soaking wet from roof and window leaks. my trunk was a lake when i got the car.
so i had to start with a few metal interior parts that needed to be stripped down, then i had to hunt down EVERYTHING else. this was in a time when 71-73 parts reproduction barely existed, materials alone cost me over 10,000$ my final cost might be 15,000$ i will never know i burned the bank statement. basically it was like having a car with a standard interior and then converting it to a deluxe, even though i had a deluxe interior to start, condition means a lot. it took me 2 years to get 90% of the parts together and restore them when i could not find a reproduction part, would of been cheaper to by another car.
so i recommend trying to get a car to start equiped with the options you want rather then try to convert a base model car into a high end car. this is part of the reason i've hesitated restoring my car further, i mean already i'm way underwater in it but i think about going out and getting a R code or M code or CJ car and starting a new project that would be closer to what i envisioned.
if you want a plain jane 71 and let me tell you its REALLY cool to see them at car shows because they are rare everyone has a higher end car or a clone, i love the I6 cars also they look so different under the hood, then you'll just restore and replace what you have, otherwise if you want a deluxe interior to upgrade a standard interior you looking at 12,000$ in parts.
so really define what you want, somebody already starting messing with that car putting the mach 1 hood on it. but i'm sure they didn't use the correct mach 1 hood springs to replace the standard hood springs. the mach 1 hood is much heavier then the stock hood and needed beefier springs to keep it from falling on your head while you work under the hood.
so again get the car in your hands, jack it up get it on stands, get under it and inspect everything take pictures. take a screw driver and start poking around get the loose undercoat off and look behind it.
then look at the engine bay, look around take pictures. look at the condition of the wiring see if the wire insulator covers are dry rotted, i found a TON of dry rot at exposed connections and plugs, half my harness cracked apart just disconnecting it. the covers are important because they are color coded so take pictures.
you might want to power wash the car all over just get all the dirt and junk off and see what you really have.
then go through the motor if your keeping it. its going to be a learning curve and money curve.
I've re-adjusted my expectations many times and had to compromise.
some people go into a project like this expect to wash all the grime off the car and have it be perfect underneath and all it needed was a little elbow grease then john cusack gets the girl and drives off into the sunset in a black camaro.
my movie dream ended when my mint 72 mach 1 showed up on a flat bed with 4 flat tires and a hornet nest where the dome light was suppose to be.
just temper your fear and excitement, go slow at first see what you have and what you want to do, get lots of reference material together then start with the least intrusive stuff looking at things and looking at diagnostic gauge readouts.
Anything can be fixed, you could start with the roof of a car and build a car out of it, but it will take time and money and sanity.
always relax and take a step back 'don't panic' we can and want to help.
I need to really prioratize my actions and think about my personal skills to see if this is something I want to jump into
