A lot. You can either do a 5-speed swap from a Sunfire/Cavalier or a 6-speed swap from a Pontiac G6. The 6-Speed swap is much more expensive and takes extra effort. The easiest route is the 5-speed F23 swap. You can't use the F23 that came in the Alero's 2.2 or 2.4 though. It has to be from a 2000-2002 Sunfire/Cavalier "2200 SFI" engine because they share the same belhousing pattern as the 3400 which is called the "GM Metric Pattern".
You'll need at least the following to make it work:
- Manual Alero Subframe
-Manual Alero interior trim pieces
-2200SFI Sunfire/Cav Trans
- Tuning software
There's much more than just this, but I can't think of it right now.... Check this link out:
http://www.grandamgt.com/forum/showt...ght=speed+swap