i'd keep it stock, (with a 5 speed though) but, I'm old now.   

Hmmm given the low inlet flow rates of the log head (145cfm with porting) it'd be pretty low powered anyway I think.     Custom manifold on the 2v head would work a lot better,  but it'd be cheaper to do a triple dcoe weber style efi setup with that.   Hmmm can always dream of stupid but cool things ford six related.

someone may already do a triple throttle body setup, but most would just go the 4 barrel below
  https://www.ebay.com.au/itm/163422319601

you wouldn't do that with a triple set up, i''d expect they'd be flow benched to be fairly even, and likely be better on fuel on a stock engine as is with better power and response. 

https://www.efihardware.com/products/2883/Pro-Race-Mazda-20B-ITB-Kit-with-130160-Spacing   Ditch the manifold and run a custom fuel log, this could be bolted to a tri power style log head.    I wonder if a Haltech could be programmed to run the middle injector at low and medium throttle and the kick the other 2 in at wide open throttle, just like how the carb setup works.

That is awesome, going to look into that one for sure

there's a NZ based forum that has a lot of custom stuff.. here's the DIY Fuel Injected Thread 
(note, if you join there,  read the rules, you can't post in their project threads, they have a separate "discussion thread" also have an intro thread like we have here but it's one continuous thread for each person to post after the next) 
https://oldschool.co.nz/index.php?/topic/34850-diy-fuel-injection-thread/page/121/#comment-2715941

3 ITBs from something that measures up to the right cubic inches would be kind of cool. 
few guys over there doing custom 3D printed in plastics or metal adapting e throttles to custom engine builds. 
no idea what's in that EFI thread, but no doubt whatever you've thought of and what you'd never think of would have been discussed/discovered in it. 

Hmmm maybe just plug up the middle hole and run 2 of them similar to the old Holden 179 X2 red motor with the twin strombergs.   Could poke a pair of 5 inch chrome aircleaners out of the bonnet like a tunnel ram.

https://www.classicindustries.com/product/of5970.html?srsltid=AfmBOopJShH31UIiGYpH4-SrAuCLskDieL5qujshMkkFtBx9am8jzxsp   I wonder how this would go on the log head with triple holley sniper 1100's on it...I guess you'd have to slave the 2 outer TB's to the middles ECU to stop the ECU's from clashing.   Would be a very interesting setup indeed...guess I'd have be a guinea pig for this sort of setup.

I reckon it'd be fine with a 250hp 4.1 litre, I doubt it'd go past the 300lb torque limit.   Not overly fussed, it's only a temp box to save me from the 3 speed...I really dont understand what people where thinking when they invented column shift manuals...