Welcome Jim!
There are many
experts on this forum, among which I am
not, but perhaps I can be of some help.
As you described your project, I would say that MS2 v.3+EDIS4 will meet your needs. I would also point out a couple of things:
I suspect you already know that you will need a 36-1 crank wheel to trigger the EDIS module..... (not mentioned in your post)
There only 2 wires required between MS and EDIS (PIP and SAW) which makes the connection very easy.
You will need a wiring loom, which you can build yourself, or purchase assembled.
Now, for my personal preference, which you are
not expected to follow!
I have used the relay board on at least one of my projects and didn't care for it. I found it just as easy to purchase an 8' pre-made loom from DIYAutoTune and wire MS directly to my injectors, ignition etc.
I hope that helps a little.
Ken
1979 Corvette - 383 CID SBC w/ Holley Pro-Jection 900 CFM TBI, 4-85 lb lo-z injectors & Walbro 255 pump
MS2 v3 w/ms2extra 3.4.0 Release
36-1, Delphi LS2/7 coils in wasted spark, driven by v2.0 logic board from JBPerformance
Spartan Lambda Sensor from 14point7