Sorry that I forgot to add that last summer I put in a new 150 amp alternator when mine went bad. Also put in a Optima AGM battery. The MIO-MMRAD-CK-67X radiator from Summit was only $298 w/tax and specifically made for 67-72 C10s. I ordered the Mishimoto dual fans from Jegs today. 2600 cfm total.
http://www.jegs.com/i/Mishimoto/690/...PROBE/10002/-1
Much lower price than Mishimoto and it comes with the adjustable controller installed. Only $287 w/tax (military discount helped a little). I'll post again here once the fans are installed to let you know if they work well. Ship date is 19 May 2017.
I also recently put in a new temp gauge so I know it's working. Engine temp good until it's in the 90s outside and then it's half to three quarters towards hot on the needle after about 5 minutes at idle.
So what's the best way to know exactly engine temp is by degree?