Will a cab from an1988-1998 chevygmc extended fit on longbox frame the same years and short box perfectly?

No, a cab from a 1988-1998 Chevy/GMC extended cab will *not* fit perfectly on a shortbox frame of the same years. While the body mounts might *mostly* align, the extended cab's longer body will overhang the shortbox frame's rear. This would require significant modification to the frame, body mounts, and possibly even the cab itself to make it work. It's a major undertaking, not a simple bolt-on swap.