Tried to search but got conflicting results.

Will a 99  2.2 heads work on a 96 block?

The head gasket part numbers are not the same so I am thinking no..

Short answer is yes. Match head gaskets to the heads if installing on a 2.2 block.

If using a 2.5 block use head gaskets for the turbo 2.5.

Yeah it can be done. I think you need to modify the headgasket or get one compatible for this swap if cometic or six star make one.

Short answer is yes. Match head gaskets to the heads if installing on a 2.2 block.

If using a 2.5 block use head gaskets for the turbo 2.5.

I should have added, both are 2.2l.

Any problem with the 96 bolting to the 99 trany?

no problems, it'll bolt right up.  you'll have 4 fasteners instead of 8, but those 4 line up just fine.  it basically attaches like a 1998 and earlier engine, rather than a 1999, no big deal.

 

the main issue is that you're bolting Phase II heads to a Phase I block and need to be careful of the holes lining up properly.  it's been like 10 years since i've done it so i don't recall specifics.  you would want to ask which headgasket to use.  maybe it's a non issue in this case or with EJ22's, but i'm uncertain.