I do know that the S2 trannies in the F-bodies *should* bolt up to your motor. Now, the trick is going to be the flywheel and torque converter. S2'* have a different stall speed, since the 2 engines make their power in totally different areas of the RPM range. IF you can get the S2 transmission from a boneyard, and be able to use a TC from an L27 in there, you *should* be golden.
I just thought of another issue...motor mounts. As it sits right now, your motor does not have provisions for a mount on the rearward bank (based on FWD orientation). Only on the front bank side does it have one, so you may want to think about a girdle-style mount that mounts on the crankshaft end of the motor, and spans both sides.
Or you could hold out and get you an S2 from an F-body. Most problems solved that way
Welcome, downwardly mobile yuppies, to the dawn of the Age of Nefarious.
1993 SSEi - FrankenJinx - dead and gone.
1994 SSE (136K strong) - 180* t-stat,HD alternator, most unequipped SSE on the club, XM radio, Kenwood CD/MP3.
2006 Chevy Malibu Maxx LTZ - Custom 2.25" manifold-back exhaust w/FM-80. Probably the only Maxx with this system.