First time I stepped on here I saw two Mercedes lumps down below - at least one was installed in 1966 in Z&A. BY 1973 they had been replaced by a firm called Barth (Sp?) and were on their last legs, Dick spent half his life down there trying to coax them to give enough power.
Spangles did a deal for their replacements in early July 73 and they were installed on the poop deck. After then I only ever made fleeting visits, and the power plant was not something I was ever interested in. Jim, or Mike are the people to ask about this - or even Nigel Tibbles. Sorry, I cant be more detailed.