Hi Mal,

I needed a "chunky" rectifier a few years ago and managed to find
just what I needed at the local welding supply shop.  Most of the
wire-feed (MIG) type welders have a monolithic high current,
low voltage rectifier brick.  Good for 100 amps or so with a
voltage rating of 50 or more.  The price wasn't bad either.

73, J.B., VE3EAR - VE3WZL
Solar and wind powered
Lowfer " EAR"  188.830
EN93dr

http://www.hurontel.on.ca/~weazle