When I finished my v6 to v8 swap in my 97 ram about a month ago I eliminated the evap crap, it's not hooked up anymore and I just plugged the holes where it connected to the vacuum ports etc. Pcm doesn't seem to care and it runs great. I used a pcm from a 98 truck that had manual trans since my truck is manual trans. I talked to a guy who used a v8 auto computer when he did his swap and he told me the check engine light came on with auto trans codes since he was running a manual trans. But it otherwise ran ok he said. So I know you can do it.