Intake had a slight leak, I rebuilt the TBI , and that was cheap to do .
I let the truck sit for about 24 hrs after putting it back together , then re torqued the intake bolts again bout 40 lbs.
Check all your vacuum hoses as well, any cracking or chalkiness replace them. infact i would recomend replacing all of the vac hoses that come off the back of the intake, the premolded one's going to the carb and egr i left alone but i tested them to make sure they weren't leaking. runs like a champ now
Also if you have a oil leak you can't track down there is a good possibility it's the oil sending unit that lives below the distributor. once the thing fails it will give you an erratic pressure reading and the oil will begin to go right through it .

 

well mine didn't have any dampness on the floor however i noticed on the bottom of the firewall in the engine compartment there was , the other morning it started to fog the windshield so heater core is getting replaced now too.

 

Same, mine turned out to be the heater core, noticed water on the ground.... It leaked inside and out the passenger door sill.

 

Ah yes. They are so fun to change too right?