1966 C10 Beginner

[Luvmy66]

Hey everybody! I’m new around here just wanted to introduce myself. Love this site. I have a 66 C10 that my grandpa bought new in 1966. Just recently took my maiden voyage in it it’s been down for several years now. Needless to say I am stoked to be driving it again it was one of the trucks I learned how to drive on. I have a couple questions if I am in the right place for that. 1. I have a red light on on the dash it’s the one above the H in the Temp portion but it only comes on when I start it then goes off after a while. Don’t know if this is trying to tell me it’s hot or what but the engine is cold. 2. I would like to have some good manuals on it. Which ones should I get and where to get them? Thanks guys look forward to hearing from yall.