Very cool. That's thinking outside of the box. Those Accufab TBs flow good, the elbow would be the limiting factor in many cases. I've used some of those before, some of the 4150 mount 4bbls ones are very low, can squeeze those into tight places.
As for what the HP or dominator ECUs will work with, you can start here, the 'selection guide' :
https://documents.holley.com/efi_sel...chart62914.pdf
Here's the DBW TBs & pedals that work with the Dominator:
APPROVED GM THROTTLE BODIES:
GM Part # - 12570800
GM Part # - 12570790
GM Part # - 12580760
GM Part # - 12580195
GM Part # - 12605109
GM Part # - 12629992
GM THROTTLE PEDAL ASSEMBLIES:
GM Part # - 10379038
Lokar Part # - BDBW-GM02
APPROVED FORD THROTTLE BODIES:
Ford Part # - 7R3Z 9E926-AA (GT500)
Ford Part # - BR3E-9F911-AB (Coyote)
Ford Part # - BR3Z-9F836-D (Coyote)
FORD THROTTLE PEDAL ASSEMBLIES:
Ford Part # - BR3Z-9F836-C (Coyote)
Ford Part # - BR3Z-9F836-D (Coyote)
APPROVED CHRYLSER THROTTLE BODY (DBW):
Chrysler Part # - 04591847
CHRYSLER PEDAL ASSEMBLIES:
Chrysler Part # - 0486 1708 (558-417 Specific)
Chrysler Part # - 0486 1714 (558-418 Specific)
As for non-DBW TBs, basically boils down to the TPS, IAC, MAP, CTS, type, and you can mix & match. There are drop-down boxes to make selections. There is also a custom selection where you can enter parameters for each type of sensor, but some combos may be limited due to algorithms' complexity. But if you stick to say all Ford stuff, or all GM stuff, you would be in good shape, especially if you don't mix 'generations' or OE combos.
You can download the Holley EFI software and play with it, after you dig around, you can figure out what works and what doesn't. If you really wanted to, you can drill down to the ECU pinouts, and make your own harnesses (I did). That way you don't have a big bundle of wires that you only need 60% of.
I wouldn't bother cutting the one you have up, would just get the single mouth unit and sell the one you have. The single mouth one also looks like a better flow path, and there is a diagram showing height, not sure on the dual, there is no diagram.
You have seen the Edelbrock elbows right? It's lower, and is only .56" above the 4150 flange:
https://www.edelbrock.com/ultra-low-...ack-38473.html
The Sullivan single mouth is 3.5" above the 4150 mount flange in comparison. (again, not sure on the dual mouth, no specs)
You do also realize that with a DBW TB, there is no IAC. That saves space and cost. MAT sensor mounting also has some particulars, keep that in mind too.
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