I stopped at an auto parts store this afternoon and looked for different length studs. Nothing they had there would work any better.
I was leaning towards the Heli-coil fix anyway but wanted to rush the job and get it all done today. So I then paid ~ $29.00 for the 3/8 -16 thread repair kit. Ouch... Now I have enough extra helicoils to do every Model A head in a three county area.
I just might Red Loctite the heli-coil in the head just for good measure and it should be a fix that should last for my lifetime. Hopefully this will also make the Pro Loctite guys OK with me.
BTW, I see this Helicoil kit is now using China made tools and the insert coils are made with "global materials". I hope my 100% USA Model A Ford will not have an allergic reaction to this.....