Auto body repair & detailing: Paint Removal Chemical, grit sandpaper, paint stripper

Question
Hey brain thanks for your time.  Well I'm repainting my 90 gmc jimmy and I just want to have the truck preped before I take it to the shop to get painted.the truck now has a very very badly faded paint job and from my sanding I can tell that its had four layers (primer;factory paint; primer; aftermarket paint) respectively.   My question is if I should sand it all the way down to the metal or use chemical paint removal.  The roof has a lot of rust all over and small holes from the roof rack that has been removed.  If chemical paint removal is an option, is there a specific automotive grade or just any paint remover from home depot would work?  I was planning on just doing the roof because that is where most of the damage is.  If i'm already doing the roof should I just go ahead and do the whole truck?  again thanks for your time.

Chuck

Answer
I would strip the areas that are needed with paint stripper from an autopaint supply dealer. Only strip what is needed because this is a very messy and time consuming job. I only strip paint if it is the only option left. try sanding out with 80 grit sandpaper first.


            Hope this helps
                    Brian