Hello, Bob. I too am loking for a diesel MB right now to try and convert. I am planning on fabricating everything myself.
The tank (or atleast modify a junked one)
The heater pickup
Hose in hose setup
Heated filters
Return lines
Electrical circuitry

(all I need is the money :'( )

I see no reason why wvo would ruin a diesel engine. Not like were putting pump gas in.
Maybe we can trade emails every now and then and share ideas/problems