I am also looking into the same thing. As Andrew mentioned, Megasquirt is the cheapest and it will do the injection and also the timing. You eliminate the advance in the distributer and allow the Megasquirt to control everything.
I am going to do it in phases to break up the cost and to fully refine the results. Also allows you a fall back point if something does not work as expected.
Phase 1. I bought a 5.2L Magnum engine complete from oil pan to throttle body for a whopping $200. That raises my compression ratio to 9.1:1 right there. Putting EQ Magnum heads tapped to fit LA intake with Mr Gasket 5805 .038 head gasket. Carter BBD with stock electronic ignition. Add Carter electric fuel pump.
Phase 2. Replace ignition with Megasquirt handling all timing and blocking the advance plate in the distributor.
Phase 3. Retap the EQ heads for Magnum intake and put the Magnum throttle body and injectors back on. Have Megasquirt handle handle the injectors as well. Replace fuel pump with high pressure one and add return line to tank. Change throttle pressure linkage to a cable system to keep the transmission working properly.
Will keep the old numbers matching block just to say I have it.
Part of phase one is also adding a lockup A904 modified for higher speed lockup and a TF-2 shift kit. I am skipping the overdrive right now as it is not cost effective.
Craig