I have a 87 na fc and I was wondering, would I be able to put a s5 tranny into my 87 fc? If it is possible what would I need to replace? Like would I need the crossmember and stuff from a s5?

 

Yep, transmission, crossmember, Y-Bracket to get it to bolt up.

...and preferably: new transmission rear seal, Turbo throwout bearing [it fits NA cars too], new clutch kit, and new transmission mount blocks. [All of these are optional, but preventative maintenance is good ]

 

So would I need a s5 clutch or is the original fine?

 

Your original clutch will be fine. It's just a thought that it might be worth replacing if it's older.

 

Ok cool, thanks for the help man