Tach Inop after engine swap
 

Greetings! I "inherited" PorscheRulz '88 944 after he blew the engine. I knew of an '85 1/2 parts car with a good engine. I had a local mechanic swap the engine AFTER installing new timing belts, etc.
Anyway, after I got the car back with the swapped engine, the Tach no longer works. I would LOVE to get the tach working again, any ideas? I had a BMW/Mercedes mechanic suggest I swap the ignition coil wires, but I am skeptical of this. In addition, the light (arrow) that "advises" you to shift does not work, but I am assuming this is because the tach is inop.
Also, the engine oil level light is on all the time, even though there is plenty of oil. the oil pressure gauge is fine (after I replaced the sensor at the oil filter he broke reinstalling the engine!)
Thank you for any advice in advance.

RE: Tach Inop after engine swap
 

the simplest answer would be to triple check all the sensors and connections and wiring