1972 does not turn over when hot

[scottb5y]

Hi,

My 1972 will not turn over after being driven for 20 minutes or so. I'm pretty sure it's a bad set of contacts or something like that in the ignition switch, but wanted to see if there were other things to consider between the key and the starter. Meaning is there a relay in there somewhere I don't know about ?

I know it's not the starter because when this first happened, I wanted to rule out the start/solenoid. So I ran a set of jumpers (1 from the solenoid and 1 from the start main lug) up to the fenderwell and capped them off. Now when it gets hot and fails to turn over, I pop the hood and just jump it. It works, but a bit of a hassle and not very easy for tohers to drive my vehicle (good excuse I guess).

It's the original switch so my guess is it's worn out and something in it does not like the heat.

Are there other things I should check first ?