The 230 is a shorter and narrower engine. Nothing interchanges with the 235. Intakes and exhaust are available, the 230 and 250 are interchangeable. The exhaust manifold on the 230/250 has a poorer quality casting than the 235, tends to crack easier, so inspect carefully. Last trip I made to a local junkyard they had a 250 with manifolds still on it. The HEI from any GM six (75 & on) is a drop-in. The SM420 will bolt to the bell housing from either engine, but there is a difference in clutch linkage with the newer housing. Tom Langdon at
www.stoveboltengineco.com sells a motor mount kit that makes the swap easy.
