Found my swap! b18a1 junkyard spec
 

My friend who has the same car as me just got an integra b18a1 from the junkyard and is rebuilding it. He also showed me the secret integra that no one knows about at this other junkyard. They want $450 for the full swap. The engine has 140k on it, but we are going to rebuild it.

Now my actual questions:
(this is going into a 90 civic si hb)

I've heard that you have to push back the firewall a bit for the alternator to clear. true?

My friend is putting a vtec head on his b18. How much of a power gain can he expect? is it recommended?

has anyone else done a similar swap like this and can give me any pointers? does anyone know of good support sites for b18 swaps?