Crankshaft Position Sensor/Timing

[Silverbullet91]

I'm helping my buddy replace his blown KA in his 1991 240sx. The "new" engine is another KA. We have installed the engine and it cranks but it will not start. I checked the engine for error codes and got error code 11 which is the Crankshaft Position Sensor. Is the CPS built into the distributor (the 4 wire connector that plugs into the side of it) or is it on the back of engine or on the transmission somewhere?

Also, when I put the distributor on the motor does the crank need to be on the 20 degree mark since stock timing is 20 degrees, or does in need to be at TDC?

[D1SR240]

motor should be at 0 degrees and the distributor should be on the number 1 piston