3550 into a 96 cobra

It's not bad, but you need some specific parts.

Bellhousing: Either Lakewood (if you plan to go 11's or better) or a Tremec Aluminum bellhousing (cheaper, easier to install).

Shifter: 3550/TKO have a specific shifter

Crossmember: Tremec and/or D&D Performance sells a crossmember mod for the 3550/TKO.

Your stock clutch will work, and your stock driveshaft will probably be ok too. I highly recommend calling Joe at D&D for parts and questions - those guys are top notch.

Good luck.
Bob