everything will depend on 3 things
1) the condition of the car. if the rust is minimal and nothing structural, then you can put off the body as long as you want.
2) your skill set.
3) your time. I have a lot of projects i wanted to do this year for the car that i just never found the time for.
for me i had zero skills just a few years ago. i decided to tackle what i could reasonably do myself and build up confidence.
I started with the interior, i learned upholstery. i redid all my seats, then moved on to interior panels, headliner, then into the dashboard.
i did minor electrical repair, just the basics. This led to the car being drivable, and also put my life in danger a few times because i didn't know enough about other things that were wrong.
it took me a year to do the interior most of that time was collecting parts i didn't have, slowly i built my skills in restoring parts one by one. i learned very basic welding at this point.
with the electrical done and the interior 90% restored, i took the car out on the road, on trips and discovered engine and brake problems.
this lead to my first en-devour into engine repairs i had never touched an engine before, i learned to do a tune up, and i learned how carbs worked and how specialized engine tools were suppose to be used. I replaced my distributor and thermostat and had many bumps along the way, and got the engine running ok, not great. I did my first oil and filter change. and changed my fuel pump.
with more and more driving time under my belt, i then turned my attention to my brake issues. what started as a simple brake service turned into an entire brake system replacement. 100% replacement of my original system needed to be done, and i did it myself.
this confidence allowed me to go back to my engine issues, and with a better skill set i learned my engine was in fact terminal, this led to me removing my engine and transmission to be send out for rebuilding.
once the engine was out, major structural issues were found and the body was sent out to a metal fabricator for 6 months of repairs. The metal fabricator reported back to me as a car hobbyist that my suspension did not look good either.
when i got the car back, it was at that point i felt confidant in my skills enough that i completely gutted the car down to the chassis. i striped everything the interior the wires, dash, it was just a shell.
then i spent the next 6 months restoring the chassis and looking it over. I even did paint work.
in the end i replaced:
body parts.
The entire fuel, and vapor return system, from the tank to the carb and from the tank to the fuel vapor canister.
i rebuilt the entire electrical harness for the car.
The entire climate control system, including A/C.
the entire brake system.
the entire suspension system.
the power steering system, including column.
The glass.
then reinstalling everything back, dash interior.
engine was rebuilt.
transmission was rebuilt ,but with issues, thanks to a disreputable transmission service place, forcing me to rebuild the valve body myself.
right now for the winter projects i'm rebuilding my rear axle from the ground up so the restoration never ends.
I hit every single major system on the car and basically replaced it.
all this in 5 years starting with no tools and no skills.
the great part is, all my skills i learned working on my restoration was applied to my daily drivers in the form of suspension, brake, A/C, electrical, and engine, saving me some money and gaining more skills.
So start where you feel comfortable, you don't have to start by ripping a car down to the ground and starting from scratch. I would say that is a bad place to start and you will feel overwhelmed very fast and you will become depressed and scared as a whole. Start small. start with documentation. lots of documentation, learn about the car, learn what the car needs, tackle one project at a time. remember if you take it all on at once it will cost you alot of money, time, and space. a car taken apart will take up 4 times the amount of space as the original car.
at my height of restoration my entire basement in my house was filled with car parts, that spilled out of the garage. 2 years later after major work I'm still throwing stuff out.
stay steady, stay focused, start small, get lots and lots of reference material, take lots of pictures!
Oh never throw a part out until you have found the correct 100% replacement for it. you will need the original part for reference and it may have parts attached to it not included with the replacement.
never every throw a part away even if it is broken until the replacement is found and 100% correct. i blew a 1000$ on that type of mistake.
Remember the forum when you need a shoulder to cry on.