Best chassis for the 68 Resin would be the AMT 69 Cutlass 442. It is one of the best chassis out there. many modelers use it for any GM A body chassis. I have used them under GTOs, and plan on using it under a 68 chevrolet 300 I have planned. Tim
Ertl American Muscle makes several GS and GSX models. Try EBay. I picked up a 1970 Buick GS 455 Black for $20 + shipping.
I have a new in the box Revell 70 Buick GSX that I am never going to get done if anybody is interested. Thanks, Bob.
AMT 1966 Buick Skylark GS 3-1 Kit #6566 on Ebay Wow! and again WOW! and backwards WOW! That's a lot of money! $390.00 & 37.75 shipping Probably the nicest and most origonal kit in existance. Mine the boxes show normal ware and parts are not all on the trees. Can't even amagine that kind of money for plastic kits. WOW! There is just a box and directions listed for $70.00