Restore original parts or leave them alone?

[Survivor 69/Z28]

I have a 69 Z28 that is truly a time warp. This was not a barn find. But a car that has been treated really well over last 38 years by the previous 2 owners.
Over 90% of the car is all original. 30% of the paint on the outside is still original. The body paint was freshened up some time in the late 70's. The interior is untouched but looks almost new in appearance. All the sheet metal is original. The entire drive train has never been monkeyed with or removed from the car. Still has the "O" stamped on all of the rocker arms. Still has the original fuel pump and starter. So I think you catch my drift that this is a pretty nice original old car that has been very well taken care of over the years.

But here is my dilemma.
I want to clean up the underneath of the car and the engine compartment. For example, clean the frame the best I can and paint it or touch it up. Clean the differential and paint it. I have already started taking a few engine compartment pieces off and have repainted of course back to the original colors. I have left the original stickers alone.

My big question is....Is it a bad thing to freshen up some of the original parts on such a survivor type car? (some parts just need to have paint on them so that they don't rust...in my opinion)
To me, I am doing things that anyone would do with the upkeep of their vehicle. For example if the paint has warn off the differential then you simply paint it.(Which it has..)
I have never owned a car like this, so I want to make sure I am doing the right thing. Of course its my car and I can do as I please. But on the flip side, I do not want to hurt the value or anything like that.


Thanks for the help!

Anthony