1976 suburban K20 manual, no crank

[DEK5]

Recent new member on the boards with a question about my 76 k20 burb with a manual transmission. Truck is just a hunting rig that a friend & I use around his farm, bought it about 4 yrs ago and we've been fortunate that's it's not needed any TLC other than new shocks and a window crank. This year we thought it worthwhile for a quick tune-up since nothing's been touched in years. New plugs, wires, battery, oil change, clean air filter and a bath to get rid of a couple 100 lbs of unneeded mud and junk.

Immediately following all that the burb ran great, started with no issues and no hesitation, smoked a little but no worse than it did before so all is good. Fast forward 2 weeks and now it won't start. Power to the lights, wipers, rear window, etc.. but not action on the starter. If you depress the clutch you hear what I'm guessing is the safety switch engage but that is it. I've checked all the connections and everything appears tight, I cleaned that connections I could get to without major dissassembly but perhaps I need to clean/check again. Just trying to see what the basic first steps are to trouble shoot or if anyone has had a similar condition. If you get the truck rolling and pop the clutch for a compression start it fires and runs as good as it did beforehand but once it's shut off your stuck again with no crank.

Any input is appreciated and welcome, I like to tinker and can normally figure things out but I am by no means a mechanic so even if it sounds like a newbie suggestion feel free to throw it out there. Short of pulling starter to have it and the selonoid tested I will probably try to jump the starter tonight to see if it spins. Thanks in advance for the help and I look forward to being on boards more, looks like a great Fourm with a lot of information to learn from.