An OBD I H22 can be swapped into a '90-to-'93 chassis using all the stock engine mounts. The exhaust system is a direct bolt up (aside from being painfully small) with the Prelude's downpipe and cat. Your original fuel rail will work on the H22, and you also won't need to swap the 6 and 11 pin on the ECU. If your oldie has an automatic, you'll need P/N 60831-SM4-300ZZ to mount the manual transmission. On the plus side, the earlier chassis is about 100 pounds lighter, and if you're picky, you can still get four-wheel discs.