my 1966 GM c50

Looks like its a single resevouir, pretty small cap with a single bolt holding it down.

Is this also a single piston setup? If so do I have any options on a master cylinder replacement with dual piston and would there be an option with vacuum assist?

Thanks




[color:blue][b]Dan and Rambo the Dog[/b][/color]
1966 GM C50 Dump
1998 k3500 GM 6.5L TD 4x4 Crew Cab Dually