You can use the the rear flare bed seal from 2nd gen tacoma ( 05-15). You need 4 seals total. The Tacoma one is a little bit longer so need to cut it to fit.
94s has separate ECU that control the transmission. Should it be easier to leave the transmission ecu in place and use Haltech ECU to control the engine.
If you in the 2wd and the front hub is unlocked, the only the thing that should be moving or spinning is the wheel hubs. I would take the font hubs out and inspect the wheel bearings
95-97 have the crankshaft sensor on the oil pan. like fj80oregon mention above, you need to take out the timing chain cover and swap the Crankshaft Timing Gear, Crankshaft Rotor, Crankshaft Sensor, and Engine Oil Pan from the original 95 to the new 94. Hope that help
I know a guy here onMud with a 60s with OM606 conversion. I belived he run a 606 with 603 pump and SRT8 transmission. He make his own adapter to his 60s split case.
I was looking into that route but om606 and parts are harder and harder to find. The best way get an om606 is to find a crash...