Tune-up questions

[RRRandy]

I just bought this 86 944 turbo. I’m trying to do the regular tune-up maintenance to it. Belts, plugs, Dist cap and rotor, filters and…what else? Any suggestions of what other items to look at that may need replacement or upgrade?

My plan so far:
NKG plugs- BPR7ES where can I get these?
Any recommendation on an upgrade of plug wires?
Dist Cap and Rotor – is there a better one than the stock?
Do I really need the timing belt tensioned with that special tool? Does retentioning required everything to be taken back off the car?
Should I do the water pump? The water temperature hits the upper bar(not the red) but cools down, even with the AC on. That seems pretty strong for Texas in August(100F ambient).