As t-man said…. 48RE mucho better…. and his advice spot on. IIRC the 47RE early builds still had the data plates on the timing cover, the newer it was a white decal on the valve cover.

I’d be very surprised if it still had the “walker pump” on it…. The OE lift pump was attached to the back of the fuel filter housing. I used to grab a small hammer to perform “cpr” on them when they’d come in on the hook as they’d fail often. Didn’t hurt anything in my experience, but obviously aggravating when it occurred (no start/eng dies). Around 05 they came stock with the lift pump in the tank and “retrofit kits” were made available for the older trucks and most I see anymore have been “upgraded”. If it hasn’t been upgraded I’d be carrying one under the seat

A/C will always be a few degrees cooler on drivers side…. Nature of the beast. Temp gets too different from side to side = low charge.

Injector life…. Sure swapped alot of sets around the 180-225k mark. If you free rev it and it comes down to idle nice and smooth that’s a good thing. Rev it and it hangs at rpm and tumbles back to idle unevenly that’s a sign of things to come. I’m not a huge “additive” fan, but I’ve seen CRC DIESEL FUEL THERAPY do some pretty amazing things.