Update ,,,
As Hambone so astutely noted, the truck had power issues ... no more! After Jimmy Quade suggested I take out the plugs and check for fouling (he thought one or two might be fouled), this morning I removed all six. ALL were incredibly fouled. Yikes! 6 new Autolite double platnums later (to go with the Pertronix HEI upgrade), the truck runs like it's on afterburner. Wow!
What a difference a set of plugs can make.
And the kid at Autozone who sold me the plugs this morning impressed me -- he seemed, for a teenager, pretty knowledgeable about such stuff. When I told him about the Pertronix, Flamethrower coil and everything else, he suggested I open the gap to .040 versus the recommended .035 to make the plugs fire hotter. Well, it seems to be working like a champ. Just a short test drive over to Milt's a bit ago was breathtaking. I didn't even have to split shift.
Happy boy!
JM