'93 won't start/crank when hot

Hello everyone, New to the site. Looked back in the forum, didn't see anything close to my problem. My '93 TC with 75,000 miles runs like a dream
EXCEPT now that's it's getting hot (85 deg +), in the afternoon the starter
quits working. no clicking no cranking nothing. Horn, headlights, radio work fine. After sitting a few hours or overnight, will start right up like nothings wrong. Friends say the selinoid is weak and the heat is effecting it.
Tried to change the starter! Impossible!! seems the exhaust manafold must be removed to get to the top bolt on the 4.6 V8?
Haven't tried setting and unsetting the alarm for possible solution.
I have a ill parent and need a dependable car!
I need to get this fixed then on to air bag replacement!

any ideas's or solutions?

thanks!!!

Make sure the starter ground is good, some times the connections can corrode.

As for removing it you don't need to remove the exhaust manifold just a bunch of extensions and patience. When putting the start back in you don't really need to have that top bolt as the earlier 4.6Ls only had 2.