im sure this has been asked before, but i been searching and trying to figure out what sensors on the block do i need. its a obd1 b18a1, i know there is 2 sensors in the back of the block, oil sending unit and 2 wire plug for coolant? there is a water temp sensor on the left side of head, right under the dizzy. what other plugs will be needed for the swap to run correctly without throwing any codes

 

The 2 wire plug on the back of the LS block is the fan switch.

Everything should plug right up to the LS block from your current harness, except for your 1 wire o2 sensor that runs by the tranny and the emissions stuff thats on the firewall.