Convertible quarter panel alignment

[JD79]

Hi guys, i am in the process of replacing the quarter panels on my 1973 Mustang convertible. These cars are very flexible! My restorer has installed the right panel already. He says that the gap between the door and the top of the quarter panel is about 3 millimeters more than the bottom ( on purpose). The car flexes a lot if you add weight in the middle, bringing the panels closer together. His theory is that if people are sitting in the car the gap could decrease and this way it will not touch the doors. Would the gap change a lot after installing all the other stuff, like engine, gearbox,front bumper etc...? 

What is the standard gap between panels? Is there a manual available with alignment measurements ?

 

[tony-muscle]

Here is a capture from the shop manual with the gaps. In my car, which is a fastback, I had to compromise. These cars are not straight anymore after 50 years so it is very difficult to get all the gaps perfect so you have to compromise. They may not have been straight from the factory as you can see by the large allowable tolerance. Leave a little bit more here to reduce a little more there. At the end of the day you should gap it to what is most pleasant to your eyes. If you want to gap it to look good when parked with no passengers then go ahead. To me that's better aesthetically than gapped to look good while driving. In any case, I am not a body expert so I am just sharing my experience. Some guys here have much more experience than me.

 

[JD79]

Thanks for your reply and the table! I will have to compromise here and there. As you mentioned , These cars have large tolerances. I had a look at some convertibles on ebay and none of them are perfect with panel alignments, so I guess I have to be less precise with my project sometimes ;-)

 

[Carolina_Mountain_Mustangs]

I have 5 convertibles 72 & 73. I am setting gaps now on a 72. I have the passenger side pretty close. Working on the drivers side. PO had put the quarters on I am probably going to have to split the quarter and move the top forward on the drivers side. Yes the body flexes and yes you need to simulate the weight of glass and stuff in doors and car. I have a totally rust free 73 California convertible and when you pick up on two post doors do not open and shut they hang up. A rusty car will flex even more. 
To move the door sometimes you have to bend the metal where the hinge bolts they did at the factory. It is not just adjust the hinges. Here is a picture of a door assembly area for an early mustang. It bends the door to align with quarter. I have watched them hit front fenders with huge rubber mallets and pry and bend doors on the assembly line. They had about 2 min. to do the adjustment.

 

[kcmash]

On a personal note, please be cautious with your gaps.  You can spend a lot of time trying to do better than factory then you discover what I did.

When my car was painted and I moved to assembly the gap between the door and the B pillar was too tight to allow the door weatherstripping to fit.  It was binding on the rubber and screw heads that hold the top of the weather strip on the tail end of the door.  So at least put the weatherstrip and casters on for a check fit before paint.

kcmash

 

[JD79]

On a personal note, please be cautious with your gaps.  You can spend a lot of time trying to do better than factory then you discover what I did.

When my car was painted and I moved to assembly the gap between the door and the B pillar was too tight to allow the door weatherstripping to fit.  It was binding on the rubber and screw heads that hold the top of the weather strip on the tail end of the door.  So at least put the weatherstrip and casters on for a check fit before paint.

kcmash

Thanks for the advise regarding the weatherstrip and coasters. We will definitely check everything before painting. Would be a real shame to modify stuff afterwards and damage fresh paint...