You didn't state whether this is the original SS paint;
a SS re-spray and what year this was done;
or a more modern BC/CC paint system.
If it's the original SS, what a testament to those that took pride in ownership...
and cared/maintained this example of an automotive-icon!!
Also:
For us back in the 1960's that either couldn't afford, nor believe, the Ford dealership's hyped-up
rebottled/relabeled car care products...(Ford had a contract with Rotunda back then)...
It looks like all of that Simonizing the vehicles sure paid off!!
Anyway:
IMHO...If you will take the opportunity to search the AGO store for Waxes, Sealants, and or Coatings...
You'll discover that there are really no "bad" selections.
Only your sensitivity to the various LSP's price-points will be the determinate factor.
Bob