57 Chevy 3100 Stepside pickup. Back in "my day" in high school, I rode the step of a 55-58 pickup, back when you could legally have a "bobtail" milk route, which my boss had as a business for many years Covered the milk crates with a wet, dark wool blanket. Put each customer's order (by memory on the route) in the milk carrier, jumped off, and went to the house, back to the step and on to the next delivery. My boss was my mentor. Got my social security # and working papers in upstate N.Y. back then, and at age 14..when we delivered our second route after a morning break (5:00 a.m. to 9:45 (coffee and donuts) and he would take a "nap" on the second route and I actually was entrusted to drive and deliver on my own. Went my way in life later as we all do, but never forgot his kindness and his teaching.
Last December I sold my '30 Model A Ford pickup I restored over three years of shop work at home, (have restored for 30 plus years) Farmall tractors (5 cubs), Cub Kadets, etc. and sold my 46 Ford Businessman's Coupe, to get the funds to purchase a very correct (Hershey 1st. Junior Award) pickup...RED..just like the one we delivered milk in the day. Respect, and memory, for the man who had passed on. My last "hooorah" vehicle..except for the 55 Crown Vic Ford I restored.
Truck came out of Fla. was in storage a long time, used very very little. parade or two..photo shoot for charity. That's about it. In a storage shed. Truck was very dried out, lube-wise, cleaned, polished and waxed to remove all residue of "salty condensation" from the seashore (seller's home on the waterfront in Fla.) and everything good to go.
I THOUGHT:

The truck had a slight "ticking" that bothered me..was advised by another restorer to put some "Seafoam in her" most likely a valve sticking. Took the advice. Put the suggested amount in the gas tank. Truck settled down in about ten minutes. I was pleased. Put her back in the garage. Shut her down. I went back out an hour later, just
to convince myself all was okay now? Hit the starter and the battery discharged hard on the gauges..growned, like it was almost dead..short grunts and quit. Truck would
not turn over more that about one or two revolutions. Checked the battery. All lights, etc. functioned well. Battery at twelve plus volts on meter. The truck will NOT start, or turn over. Ran great an hour before. Now? Sounds like the engine is seized..or something. Can't figure it out. Read the whole d***ned service manual for 57 pickup/trucks, and only came up with: Battery sulphated? Starter seizing, or locking up tight? It showed charging when at idle in the driveway. At a loss for what to begin here.
I could use advice, for sure. Thanks for reading if you have had time, my introduction...and problem. John "milkman" here on your forumn. Thank you for any advice someone might give me.