Power Source PC40 Schematic Help

[Mallard]

Hi I have a Power Source Battery Charger, Power Supply, 40 AMP, Model PC40 and I have the hand drawn schematic for the PC30. The Q2 IRF740 transistor (board 2) is burned out and has melted the 3 variable resistors in front of it. Their is 4 variable resistors on this number 2 board, all are labled 250 527m and are refered to as 250 variable resistors. I need to know what their values are and where I can buy them. Also I read on an old post that someone had the schematic for the PC40 and if so could you e-mail them to me?

Thanks Mallard