This is my question also. There appears to be no difference in the paint under the pickguard and not under the pickguard. I might not have noticed that except for the non-faded paint under the bridge cover. There’s something here not adding up.
That blonde finish is how the bass would have looked when new. The idea that finishes "fade" is misleading. They don't fade and get lighter, they discolor and become
darker from exposure to the environment, which was often smoky bars, etc. It's called "butterscotching".
If that bass was seldom played, kept in its case (which is original, btw) virtually forever, there's a good chance that the finish under the guard could still look the same as the rest of it. The overall wear seems consistent with a very seldom played, and well protected bass. The butterscotched area under the bridge cover is likely from foam mutes, as 2saddlebridge already pointed out. There is also some butterscotching on the arm contour, which could be from player sweat.
The two serial #'s is unusual but not unique, I've seen that before. And '55 is the transition year for serial #'s moving from bridge to the neck plate, which makes that particular bass more interesting to collectors. My 2-55 had only a bridge #, while my 4-57 had both bridge and neck plate numbers. Go figure.
Is that bass an original uber clean example?...is it an expert-level resto? No way to tell for sure by just looking at pictures because there are expert fakers out there who can fool the expert vintage guys, even Gruhn. I'd like to see some fine finish checking there, but that's not a for sure thing either.
Why is that dealer listing it on ebay, when there's little to no chance that anyone will pull the trigger, or even make a substantial offer? Advertising. Cheap advertising for his store that automatically creates a buzz all over the interwebz. His cost?....just the peanuts for the listing fee. If someone is crazy enough to pay the inflated ebay price he has in mind, then all the better and worth every penny of the additional associated listing costs. Brilliant!