340 has a hard time starting when hot?

Will check, was wondering if the stock cable from the solenoid to the starter is too small for 10.5 comp and 505 cubes . ??
Solenoid is about where the heater motor use to be . Its where the ''free'' no.1 welding cable reached to from the trunk mount battery /on the pass side .

I wouldn't think it would be. If it starts as you say good that second time, I wouldn't think the cable size would be the problem. I would be looking for a connection loss somewhere. How many grounds do you have on it? Such as from the engine to the chassis and firewall and such?