I have a 1994 Chevy pickup 1500 series cheyenne and sometimes when it gets really humid and dew point is high truck will not turn over, any suggestions of what to do

I need to ask a few questions: does it click and not turn over? Does anything else electrical work? Honk the horn: does it sound loud as usual? Lights and door dinger working? See my profile.

Yes it clicks and all but won't turn over, all else is working

Are you saying the starter motor will crank the engine, but it won't start? If it is a starter motor issue, read this:

https://www.askmehelpdesk.com/cars-trucks/faq-how-troubleshoot-repair-maintain-hondas-46563-3.html#post235560

You problem is probably the starter motor itself. Still check the condition of the battery cables at the battery and the starter. Look for signs of corrosion. The solenoid is the common culprit but usually not service separately anymore. Good re-man's (re-manufactured/repaired) are available for pretty good prices and usually offer lifetime warranty. Who's doing the install?