UPDATE:
Ok over this weekend I got to tinker with the truck a little.
I pulled the plugs ( Oh man.. what a PITA!!) and sprayed some oil in the cylinders. Let it sit over night, then I turned the engine over by hand with a socket and ratchet on the main pulley bolt.
Engine turned nice...free and easy! No noises made. Then I hit the starter and let it spin the motor a few times to blow the oil out.
Still turned over great with no noises.
I put the plugs in and turned it by hand again. Everything seems ok so far... good compression on all 8 cylinders. I turned the motor by hand 8 full revolutions to make sure. No binding, or noise.
So I dropped the gas tank, drained out the old gas,and replaced the fuel pump and fuel screen. I also replaced the in-line fuel filter.
Put fresh gas in the tank and started the truck, it fired up and ran great but....
There is a rattle in the engine. It is not a rod or main bearing from what I can tell. It sounds like it is in the valve train up top on the passenger side. So I am thinking it is maybe a broke or collapsed valve spring. or something of that nature. The truck sitting for 2 years might have collapsed the valve spring if it was pushed open the whole time.
I have not had time to pull the valve cover yet to see exactly what is going on.
My question to you fine people here is... Can I replace a valve spring or what ever might be broke without taking the cam off/out?
Any suggestions ?
Thanks for your time!