SmokemS

no i didn't see any valves but i took the blower motor off first which was a bunch of i think 6 or 8 little bolts then i took the cheap metal nuts around the blower motor in the engine bay and in the inside under the dash i took the two tabs on top of the box (yellow and red) which there the controls for the doors controls on the box itself and just twist and wiggle till it comes out and dont forget the bolt on the drivers side on the bottom of the box

raggmann

Got it handled this morning. Took about 3-1/2 hours.
There is no water valve on a non-a/c truck,incase anyone else is wondering.
There was nothing in the heater box to restrict flow and I ran water thru the old core just to see if there was any kinda blockage.The water seemed to run free and you can see light when looking thru the fins so the air flow didn't look like it should have been hampered at all.
Once I got it all back together,the fan seems to blow 2-3 times harder than it did before I tore into the heater box.I'm not sure what's going on there but I'm good with that.
I've got a cheap Wally World temp gauge in the cab that reads inside/outside temps. The drive home from work (where I did this job) is approx 20 minutes.I only had the heater fan on low and the temp difference inside vs outside was approx 35C.

Thanks again for the input all,