Need pointers swapping 350 TBI to 400 carb. in 87 c10

[1fine409]

I recently built a fairly nasty 409 to replace the stock 350 tbi in my 87 c10. My main hold up right now is doing away with the wiring harnesses under the hood. I am doing away with the computer (already wired the kickdown to a switch for the 700r4), but I am curious as to how many of the wires I really need to keep under the hood. I am keeping the stock gauge cluster, but am buying a new cluster of water temp/oil pressure/volt gauges instead of re-wiring the circuit board on the stock cluster, so it isn't mandatory for the original of these gauges to work, but would be nice if they did. I am running the stock electric fuel pump, with a mallory regulator for the carb, but still need the sending unit to read on my factory fuel gauge. I know I need to wire through the fuel pump relay as well, but other than that what do I need? Without Alldata, I can't find a good schematic of the bulkhead connector to see what is going where. I know guys do this kind of swap often, so any help would be great. Thanks, Dusty

[munice]

Hey Dusty,
I went through the same process in my '87, although i went from 350 TBI to 454TBI, then to a carb... So I learned the hard way about all the TBI computer mumbo jumbo. Best way to go about this is to just strip back all the loom so you know what is going where. You'll need the engine temp wire on the drivers side head, plus the oil pressure wire (dont need the oil pressure switch unless you want to incorporate it) and the ground at the water neck (one goes to the bulkhead connector other to computer). As for the fuel pump relay I basically just took the feed out to the pump and wired it to a toggle switch which in turn was fed from a switched 12v source (toggle was for listening to the radio when parked... no acc) I've got two of the underhood TBI electrical diagrams. hopefully they are somewhat legible, they should tell you which wires you want off of the fuel pump relay and everything else. let me know if you need an emailed copy or anything cheers, Andrew