My alternator wen out on my sigle cam but I have a b series alternator so I was wondering if it will fit. Looks like the same size

 

they are very close in size but i think the "ears" to mount it with are positioned differently. if you're any good at fabricating and have the tools to do so, you could probably make a bracket from some scrap steel for next to nothing.

also, as i've discovered recently the brushes and voltage regulator interchange between 88-91 civic (D15) and 90-93 integra (B18A). they are one of the most common failure points in the alternator. i would speculate that this part would also interchange in later model B/D-series alternators. if that helps any...