The converter plate was about $40 USD, I found a GM TBI at a pick'n'pull for $25 USD.

The GM TBI are rated by their venturi openings. There's a "small" one, I believe it's about 11/16" of an inch, used only on their 2.8L engines, very difficult to find. The "standard" one, 13/16" inch, used on almost every other engine and the "performance" TBI (7/8") used on their "muscle" cars and heavy duty truck engines.

They used the same injectors on the small, standard and most of the performance packages. Fuel requirements were adjusted by the Eproms in the ECU's.

I used an aftermarket inline fuel pump for a '85 Ford Econoline for fuel supply but any inline fuel pump capable of 15-20 psi will work.

The pricey part was the Megasquirt ECU. I think it was about $450 USD by the time I added on the cabling bundle and relay board (I highly recommend you to go that route as it makes wiring so much easier).

You can also use a GM ECU but it takes a bit more work figuring out the wiring. You can pick those up cheap from the pick'n'pulls.

I went MS because if I have/want to move the unit to a different engine I can simply reprogram it for the different engine with my laptop.

Wiring and fueling are exactly the same using the 2 bbl TBI as the 1 bbl TBI. They use the same sensors.

I'm also still driving my '74 280C M110 using an old Motorcraft 2 bbl from a '72 Ford pick-em-up (over a year now). Getting about 13 mpg in town and about 17 mpg on the road.

My M110 project got put on hold because I found a M117 which I am in the process of converting to MS. My wife says if something is running I'm not happy until either it's running better or not at all!