Hello matt120y!
I have a similar set-up to Wallys`Wagon
& i`m using a Holley carb & Subaru electronic dizzy. The dizzy was sourced from a wrecker & is from an 85 Leone. It`s of the same Hitachi family of distributors & requires some modifications to fit a 1200 block.
Basically the alloy boss (the bit that goes into the engine block) has to be cut down to the same length as your original dizzy.
Then the same with the dizzy shaft itself. then fit your drive sprocket & redrill the roll pin hole. Fit the base plate and locate as close to possible as per 1200 dizzy.
Use the original Subaru coil, set your timing and it should fire first go!
I`m running 9psi & 12degrees static timing, without even a hint of detonation (due to the lazy advance curve of this dizzy)
Good luck if you decide to use this distributor & don`t be scared because it cost me a WHOLE $40 bucks!!