76 Plymouth Valiant won't start

Photos might help. First job is to get it to crank on the starter.

Is this a stick or auto? The firewall mounted starter relay is central in this part of the "deal."



More on that later.

First make ABsolutely certain the battery posts battery clamps and (you replaced the ends) are clean and tight and where they clamp to the cable strands.

Make certain the main ground from the battery is direct and tight to the engine block.

Next jumper across the starter relay shown above with a screwdriver. Jumper the two large bare terminals. Be sure the transmission is in park or neutral.

If this works, it might be a bad connection in the firewall / bulkhead connector, IE where the wiring all goes through the firewall. Again, a photo or two would help