This isn't what you need, but I've used two of these on serp front engines.
http://www.tbiproducts.com/index.cfm...prod/prd20.htm
http://www.tbiproducts.com/pdf/R-4_t...08_Bracket.PDF
On engines like yours people like Alan Grove mounts.
The r4 is the Vega of the compressor world. They work, but don't work as good as others. They like to leak (As you already know) They shave piston rings off & clog up the orifice tubes & don't never ever use one of the "Variable Displacement" r4s!