/6 AC compressor on 318

Most RV-2 compressor housings have the same tapings and holes. There are a few differences in the heads with bolt bosses, some having two vs just one. As Mike said above, you'll need the specific brackets - slant, small block, or big block. The Slants often used a compressor with a larger driven pulley, this turns the compressor slightly slower. Usually not enough to make a difference. I would go with a rotary system upgrade w new hoses if I was putting something together and missing original parts.