hokay, i put an l28 in my 73 240z and i also used the 4 speed tranny and it had only one sensor plug and the l24which was in there before with the 4 speed had two sensor plugs so what do i do with the extra connectors

Are you talking about sensors on the engine, or the transmission?

The 4 speed transmission in my car is out of a later vehicle apparently, because the floor had to be cut to make room for the shifter to reach 1st and 3rd.

Anyway, the later 4 speed has two switches built in to it. One for reverse (to power the rear lights) and another for a neutral switch. Since my 71 had no neutral interlock on the starter, that connector is just hanging in space. If your car needs a neutral switch and the transmission doesn't have one, you will have to put a jumper wire in the old connector to get the car to start. I do not know when they started adding the neutral switch interlocks into the Z cars, but 73 seems too early...

If you are talking about engine sensors, that is another matter entirely.

its the transmission i was thinkioing aboot that...maybe that it was for the reverse lights

if your tranny is from a 75-76 280 the other switch is for the vacuum advance trigger. The 280 at least the 76 (cause that's what I got) doesn't use vacuum advance until fourth gear, so when you shift into fourth it triggers an electonic vacuum switch to give the dizzy advance for better acceleration.