Since it's a family heirloom survivor. I'm on the side of preservation and using it as a truck.
If it ain't broke....wait until it is and then upgrade it, but not so much it isn't your dad's truck anymore.
Keep the wheels! You may be shocked what a good professional detailer/gloss enhancement does to it. Embrace the patina.
I like driving improvements that can't be seen, like
throttlebody injection, internal engine work, and
updated lamps (Koito H4) from Daniel Stern.