Id stay away from the OBD1 motors because the distributors dont bolt the same way, the distirbutor wiring is different, the o2 sensors are different, motor mounts are different (youll have to swap brackets an such). Its not hard, just not a direct swap.

THe SOHC ZC will be a direct replacement, since it came in the EFs it will work. Everything will be plug and play.

What i meant about the timing belt and clutch and stuff is that you said you had a budget of $1000-1500. WIth that kind of money i would


1) Buy a SOHC ZC engine
2) Replace the TIming belt and WP
3) Replace the clutch (if its not new)
4) Pick up a CRX SI Transmission (better gearing
5) Buy a PM6 SI ECU $20

an you would have a fun peppy gas mileage king for under $1500.