Yeppers, glowplugs. With only 3 working, it had to crank a bit to start! But it did start. But now it kicks right off.
And as usual, when working on a 25 yr old truck, I found that the battery cables were just too bad to reinstall as they were. (I had to remove the rear battery and climb inside the hood to get to the right bank plugs.)
So, I went to town and bought a new cable to replace the cable that runs from the rear - post to the power strip. All I could do for the cable that connects the two batteries together was replace the battery bolt and straighten the clamp a little. I'm gonna have to find one of these cables somewhere. Any help out there?

That's where this kid showed up and said he wrecked his truck. I had to get everything back together so that I could play.