Originally Posted by okfulltimer
P30 Chevrolet with a 454. The resivoir was dry and brake fluid was between it and the booster.
OK, I see what you mean, yup needs replacing or a rebuild. Only thing though, I've never seen a brake master cylinder located under the floorboard, most all I've seen were mounted on left front firewall, even my old 84 Airstream on the P30 chassis had master cylinder with vacuum booster mounted on the front firewall.
Probably the best bet is to call Fleetwood and hopefully they can give you some guidance as how to access it.
Also you may want to post your question under the Owner's Corner Forum
in the Fleetwood Owner's Forum
and maybe someone there can help..
Best of luck & keep us posted on your progress