Thank you.
I fear that the seller is Jon "You Know Nothing" Snow or perhaps P. T. "Sucker Born Every Minute" Barnum.
The bass is awesome, or at least that is reasonable opinion.
It is not a '60's bass but dates from approximately 1972-1977.
It is a Guild.
It is not a prototype assuming the pictures tell the story. It is a regular production (solid body) M-85-II.
It is a single cutaway, like a Les Paul but Guild never called it that and a seller who does is clearly aiming at a market that knows very little about Guild.
I wouldn't call it in especially good shape. I have seen similarly aged instruments in better cosmetic condition and the second strap peg hole is cringeworthy. I feel the seller's pain because I too have some gear that is marked with my SSN because the police thought It Seemed Like A Good Idea At The Time.
I find the price of $4500 hard to grasp. Maybe it is one of those "but honey, I tried to sell it but no one was interested" prices?
Generally the '60's hollow body M-85's command a higher price than the solid bodies. $4,500 sounds like a price for a hollow M-85-II with both Bisonics intact and in outstanding condition. $2,500 seems high but feasible for this bass if a Sheryl Crow fan gets into a bidding war.
But that is my opinion on price and if the seller can get it I may want to place some consignments with him/her ;-)