So in ANOTHER twist, I pulled the head off for a little freshening before my machine shop shuts down. Of course there was tons of carbon on the valves, chambers, etc, but looked ok. I dropped it off at the shop and called a little while later for an update. Long story short, the cam, lifters and followers needed to be replaced as well as 4 new exhaust seats. Since the cam needed to be replaced, I spec'ed out a Comp Cams 252h for a bit more lift and duration. Nothing radical by any means since going bigger wouldn't help with the header removed.
Today's the first day of my normal driving and on the way in to work it ran flawlessly. More low and mid range torque, and I got a cramp in my right ankle because I didn't have to put so much pedal into it to go the same speed. I still have the spacer on it, and the machine shop is milling the plenum on the other manifold. I am cautiously optimistic about much better gas mileage, though that may go away when I test the modified intake. Now if it's appetite  for new parts would calm down a little.....

Don, I may play with the EFI intake later, but this is just a $25 folly on my part. My concerns about an EFI manifold are twofold. First, the "D" port mismatch, and then the mounting issues for linkage and the stock 5200. I know I could go 4 barrel, but then that opens up another can of worms with an auto (kickdown linkage). This is my daily driver, so changes must be made in baby steps to keep it on the road day to day.
I have a "theory" floating around in my head, and this is just a quick and cheap way of proving/disproving it.

I have no doubt that due to the EFI's port layout in the plenum it will flow better and more evenly from port to port. I've already been mentally sketching out a mounting bracket for the stock throttle cable bracket assy. My limitations are that I just don't have the room to put in the equipment I need to do this kind of fabrication. This would be SO easy to do with a mill......

Not a "mod" so maybe a bit off topic, but replaced the carpet over the weekend. It makes driving a lot more enjoyable than I thought it would. Less noise, somehow a few rattles disappeared, and it has that new car smell again. 
Installed an ACC carpet kit, and it fit reasonably well from the E-brake forward, but behind it on the tunnel it has an odd "hump" in the carpet that the tunnel doesn't.    Still better than what was in there, and for a daily driver I can't really complain. I rate it a 7......

So after running the kreen in the crankcase for a few hundred miles, I've gotta say you wouldn't believe what this stuff does. I'll be doing a second treatment, but this has freed up horsepower you can FEEL. Gas mileage has gone up a bit (< 2mpg), but I'd get even better mileage if I could keep my foot out of it. It's just too much fun to jump on it even with an auto. I can actually holeshotl v8's from a stop, but after a car length or two the lack of torque takes it's toll. The real problem is, I've never driven another Pinto to get an idea if what I've done has made a marked difference from stock, or has just it made run like "new" again.