Code issues which to try first?? 91 GTP using 96 m

[RUNDLC]

Hey all been a while since I was here.. I installed a 96 crate motor into my 91 GTP. I finally got her started but she is running a little rough. I did a scan and came up with codes 33, 35, 44 & 54.

The thing is two of these have mutiple things that could be wrong, I am not a trained mechanic, just a back yard wrench turner, any ideas what to try first?


Thanks