Getting ready to paint my 68 I have the car dissembled. Should the quarter extensions be reinstalled with new gaskets and tail lights and and painted on the car or painted off the car and installed later?My old gaskets were rotted away and I didnt know if they showed on the outside of the car or not.If the gaskets dont show on the outside I could paint the extensions off the car.
Thanks for your help.

I prefer to sit the extensions in place but not tightened down. That way, they get the same paint, technique, air pressure, mixture etc as the rest of the surrounding panels. There's less of a chance of a color or texture difference.

Most of what I have read on here points to if you are shooting metalic you must paint everything together, but if you are painting a solid color and wet sanding and buffing the clear (like me) then by all means it is fine to paint seperate if you want to. Just be carful on reasembly and use tape to protect the edges from scraps on reasembly ;)

After all the body work and blocking is done for the primer, test fit the extensions with the gaskets and trim down the gaskets if needed. I would then remove the gaskets and place the extension back on the car and maybe put in some small washers on the studs to leave a little gap between the extension and the body of the car and I would then run the nuts on from the backside so you don't accidentally knock them off. Once the car is painted, take out the washers, put in the gaskets and tighten down the retaining nuts and it should all fit and look just right.
Jim/Saint Louis