"90-93 LS, GS, RS had the B18A1, 1.8L DOHC NON VTEC 140hp. "
wrong, 90-91 only had 130hp, 92+ had 140 and thats when it was changed to b18b. The change in the head gave it more HP, the blocks are all the same. I believe the serial # is right but easy as it seems I can not find a reliable source of what the exact serial # is for 92-93, even the honda hybrid pages has incorect specs
and yes the head will bolt up to the block