My thoughts on replacing everything I touch....
My time has become pretty valuable and is going up in value daily it seems, so if I have to take it off the car/ truck/ appliance or whatever and it is a wear item and does not cost a ton of money, it gets replaced. good example is a few years ago my radiator cracked and I had to replace the radiator. hoses needed to come off anyways, so new hoses. to remove the radiator I had to remove the fan and fan clutch and belt. fan clutch was original to the truck, belt was 10 years old. tensioner was 15 years old. cheap, had to remove them anyways, why put them back on. so new belt, new tensioner and idler. with the radiator out of the truck, the water pump was very easy to access. cheap, and if I were to have to replace it down the road, I would likely need to remove the radiator again. so it got replaced as well.
Same for steering that I did last year. all original steering components. the steering box was damaged in 2015 when my wife decided that it was better to hang my ranger on the guard rail on I 465 than rear end the car in front of her that came to a sudden stop, so I had planned on replacing it at some time. then the rusty original line blew out. there was no way I was going to get those lines off without damaging the pump. the pump was noisy as heck anyways (even more noisy than a ford steering pump normally is) so at the time of hose replacement, I replaced the pump, box, and hoses. all new and don't have to worry about it down the road. at that point I also replaced all of the tie rods and linkages just because I was under there and it only added 100 bucks to my total cost, and the steering is now new from the steering shaft to the wheels.
If I can replace a part really quick and I have to remove it to replace another, I usually will just reuse it, but if I am already into a good afternoon or day's project on something, it all gets replaced if feasible.
AJ