'69 C20 Won't Start - PLEASE HELP!

[MarineChevyDriver]

I bought a 69 C20 about a month ago. It ran fine when I bought it, though it had an oil leak I knew about, I replaced the oil pan gasket. It still leaked from the front of the pan so I put more RTV on the outside and that sealed it up. I was driving on the highway when I started losing power and it eventually died on the road. I opened the hood the the oil was smoking from out of the dip stick tube, and also the valve covers when I opened the oil cover. I let off the pressure with the radiator cover tab and steam and hot coolant quickly evacuated out the bottom. I let a good bit of it out and then poured a gallon of water into the radiator once I could open it. It wasn't cold water as it was in the truck. I got a tow home and checked the oil, there was none in it at all. I had some leaks from the valve covers prior to that so I replaced those gaskets, cleaned up the carb, the thermostat housing which was corroded and new, cleaned the EGR valve, replaced all the vacuum hoses and PCV valve, drained all the coolant and flushed the radiator and then replaced the hoses, and finally put a full 5 quarts of oil in.

My problem: I put everything back together last night, tried to start it up and the lights came on with the turn of the key without the light knob pulled. It made a noise like it turned over with two attempts to start, someone helping me said the fan turned, but then after that I got nothing. No starter clicks, no turning, nothing. We put it on jumper cables thinking it was the battery and nothing. Got the battery tested and it's good. I put the battery back tonight and still nothing. No noise, no indications of start attempts, just head lights. I discovered that the previous owners terrible starter hookup led to the main wire being burnt by the exhaust headers all the way to the copper.

Please excuse my lack of knowledge. I'm still learning about working on older vehicles.

Here is what has been done to the truck when I bought it, so hopefully this will help shed some more light.

Rebuilt:
3 speed tranny - I think it's a turbo 350
1991 Crate 350cc 5.7L V8

New:
Tires, wheels, and brakes
Edlebrock Carb 1406
Thermostat and housing
EGR vacuum sensor (not the actual EGR valve itself, but the sensor on the front of the block that has two ports on it. one to the carb vaccum and the other to the EGR valve.)
New MSD Ignition distributor, cap, and wires
Full exhaust and headers (can't remember the brand)
Starter looks fairy new
Battery

I replaced:
oil pan gasket
valve cover gaskets
disassembled and cleaned the carb
cleaned and tested the thermostat and housing
cleaned and tested the EGR valve
drained and reverse flushed the radiator and replaced the hoses
replaced all vacuum lines and PCV valve
replaced the fuel lines with a steel edlebrock wrapped line and a steel hardline with filter


There is a pretty poor looking wiring job on the truck. There was a ground wire coming of the negative battery terminal that was hooked to the body. There are random and unused wires throughout the engine bay. The person who installed it just took the shortest route to everything, so it looks pretty bad.

I'm uploading some pics that may or may not help. I'll have to get more engine pics soon. Thank you all.