I have an opportunity to purchase Pontiac Rally II wheels and need to find out if they will fit on my 1965 Dynamic 88. Size of the Pontiac rims are 15 x 6, with a 5 inch bolt pattern (allegedly). Supposedly they came of a Trans AM. Does anyone know if these will fit my 88? I currently have 15 inch wheels.

All Trans Ams used a 5 x 4.75" bolt pattern. That won't fit your 88. Only the 64-66 Jetstar 88 used the small bolt pattern.

Pontiac offered 15x7, 5x5 Rally II wheels for 1971-76 big Pontiacs. They will fit your car if you can find them. If you want Olds centers, I think 1975-later Olds Super Stock II & III will snap into the Pontiac wheel. If not, find a set of 1980s FWD Cutlass SS-III center caps. They retain to the FWD wheel the same as Pontiac centers. The 80s Rocket is different, but if you want 60s style Rockets, repro decals for Super Stock I wheel centercaps will fit in the recess like it was made for it.