Find a NAPA store- - - -they either have a lot of the old stuff in stock, or they can order it on short notice. Have you done anything about those widowmaker wheels yet? If it's got a Hydrovac brake booster, that's a possible place the fluid is going. They're bad about leaking fluid into the vacuum chamber and never showing an external leak, and rebuilding one is a real pain! Fortunately, they're not too expensive as a rebuilt exchange unit. If the wheel cylinders are leaking, there will be wet brake fluid stains on the inside of the front tires, or between the rear duals.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!