1968 GT/CS "S" Code built March, San Jose ,Wimbledon White,
I search the forums and didn't come up with any addressing the 68 San Jose so ,,,
My GT/CS is currently being painted and a few question came up from the shop what color/finish should be the underside of the fenders be and front /rear valance be
Red oxide primer sealer (not just primer) with body color overspray from the logical points (sure this has been said in a number of threads)
This means that it makes the best sense (long term) to spray the overspray when you spray the exterior of the panel so the overspray doesn't look added later. Also consider that the guns at the time applied ALLOT more overspray than the current legal spray guns so you might have to work at it.
Of course the rear valance was painted on the car so overspray comes from the end and from the gas tank opening. Hung with two screws and not brought in at the bottom edge - into the body. Should have picked that one up from other threads (you can use the details from the 67 San Jose paint discussions) along with the doors, trunk lid and end cap details.
Front end parts were all painted off the car. Front fenders can have a medium amount to almost full coverage on the back sides
,does the underside of fenders get undercoat spray?
No undercoating from the factory. Factory applied sound deadener.
Not a requirement. In my observations only about 50% of the cars got an extra (in addition to the firewall and inner fender passes) pass over the top (bottom of the fender -along the fender to inner fender edge) and down over the splash panels of the thick nasty sound deadener. Not that 3M looking stuff that looks like black Christmas tree flocking spray IMHO
Sure you've already discussed with the shop the undercarriage overspray and anticipate the pinch weld black out process once you get to that stage