This may help, JM post from 2006.
"To clear a few questions up on the Salvadors.
1. very first original press is St. Louis, vinyl is THICKER @ (1.18mm) with NO pimples in the vinyl, the green label is a deeper shade. I only known of one copy of this press, Carl Willingham owned it, I sold it to Australian collector for £2500 in really poor shape vg-. But it was the ONLY known copy.
2.Chicago press thinner vinyl @ (1.09mm vinyl) label is a lighter shade ie (the one we have on auction)has TWO visible pimples on the playing surface, these do NOT affect play but you can see them if you twist the record in the daylight. The matrx in the deadwax reads 62771 this number is lightly scratched in and staggered. Worth 2500 to 3500 we'd guess.
The deadwax matrix on both presses are IDENTICAL ie using the same masterplate.
3. The PB boots as Ted M. rightly points out came out of Los Angeles via our friend and yours Simon S. He did Mel Britt, George Blackwell, Johnny Vanelli, and many others at the same time all have P.B. in the deadwax.
This gave birth to the story of Bob Cattaneo travelling from S.F. to L.A. to buy Simons latest fantastic find. When Bob saw all these top titles in mint condition he smelt a rat and on close inspection found P.B. in all the 45 deadwax's. Bob told Simon you can't sell these as originals. Simon admitted they looked a bit NEW, so he got George Blackwell our its sleeve and violently rubbed it on his carpet. (a ploy used on the Four Vandals scam) "there they look used now!!"
4.Then there is the dark blue label and obvious bootleg in styrene 1976 repro Delta # 100273
5. Then there is the same with a Light blue label.
Edited June 18, 2006 by john manship"