1989 Ford Thunderbird Issue's.?

Hey there; I have a 1989 Ford Thunderbird with a 3.8L V-6 engine, My grandfather gave me the care in Pristene condition (Mint) with only 24,500 Miles. We'll now that i've had the car for about 5-6-7 years, its got about 49,300 Miles now, but the issue im mostly concerned about is #1 when going up hills at a Low RPM it Pings not Severly, but its there and its been doing it/started about a 1-1/2 Week(s) ago and i've heard i could change my EGR valve and if that doesnt help then i'll try and remove my Catalitic converters because i've already got dual exhausts set up and removing the Cats will cut down on restrition (Back-Pressure) which they say is another cause to engine pinging. and also the pinging only happens when its hot outside (Afternoon). #2 while ive got my A/C running the Temp gauge runs up a little high, but whenever i turn it off the gauge drops back down, and also while driving the gauge gets a little high but whenever i slow down and let the car coast the gauge also drops down.