im putting a chevy 283 into my fc and was wondering what ecu and wiring harness i need. thank you

 

Going to need a bit more information...

EFI?
Carb?
Points?
HEI?
Auto (and if so, electronic or manual)?
Stick (and if so, what stick)?

Most likely you're carb'd, factory style HEI and a manual valve body automatic, as that's the cheapest setup, in which case, there is no harness or ECU.

You'll need, a wire from ignition to the distributor (hot in start and run), a wire from ignition to alternator (plug, not power lug) hot in start and run, as well as ground to the same plug. A wire to the "s" lug on the starter (hot in start only), and a wire from the battery to the starter lug (big one) to the alternator lug (big one) to the chassis power (fuse block).

Obviously there are plenty of other possibilities (one wire alternator for example) and gauges, tach, VSS possibly, etc, but you didn't give us any information, did you?

This is all covered GREATLY in depth if you do some searching on Torquecentral.com.