The most common current Sandens are SD7H15. The H14 is less displacement, but the body is the same size. The SD7H13 is probably the shortest (vaguely recall an H12, but same body). The distance between the mounting flanges is shorter in the H13, but ~1", as is the whole body. Otherwise, the flanges are the same. Download the Sanden pdf manual for all info. I think the H13 was used in smaller cars like a Honda Civic. I put an H13 in my 1964 Valiant slant six, on custom brackets I fabbed. I actually have room for an H15, but would now need spacers to mount one. Anyway, that car is a little early-A convertible, so what works in a Civic should suffice. The compressor will run more often but more efficient anyway. No reason to buy compressors from Vintage at high prices. I buy them on ebay, in winter when cheap. I also make my own hoses (Mastercool crimper and/or Oeticker earless step clamps). I don't see a problem mounting the compressor down low. My Chrysler minivans are like that, like many cars. That is better to keep the oil in the compressor where needed. Indeed, many people suggest that Harrison R4 compressors in many Chevy's fail because mounted high, plus they don't have a sump for oil. My M-B uses the R4 and it lasts much longer mounted down low.