Junkyard treasure 360 efi?

In addition to what Grumpus said, factory FI does NOT like longer than factory duration cams and cams with tighter than 112 LCAs. You'll also need some way to fit a crank sensor and the factory distributor that IIRC, acts as a cam position sensor, so that negates using it on a BB/RB. Don't forget that you'll need some sort of throttle body with a TPS and IAC.

If your 360 is stock, you MIGHT be able to get away with it but if it's cammed, forget it.