Tonneau Cover snaps

[76C10Stepside]

Couple questions about tonneau covers and the snaps that hold them on.

Background: I'm redoing the bed my 76 C10 Stepside. Changes include replacing the bed wood with Trex decking and unpolished stainless strips, and a black spray-on bed liner. The bedliner will cover the top rails and the top of the tailgate.

This truck had a tonneau cover on it at some point, and still has all the snaps on the bed. I plan to remove all the snaps before applying the bedliner. This leaves the decision of whether or not to replace the snaps. I don't have a tonneau cover, but maybe a future owner will want one. So, it's down to these options:
a) Replace the snaps
b) Leave the snap holes
c) Weld the snap holes shut (very remote possibility)
Question #1: What would YOU do?

Question #2: Is there as "standard" spacing for the snaps? If I install new snaps in the old holes, and later I or another owner wants to install a tonneau cover, will the snaps on the new cover line up with the snaps on my truck?

Thanks!