There's a much simpler way to adapt a divorced OD than using the BW unit. Look at the Laycock De Normanville unit that was used on Jag, Austin-Healey, Triumph, MGB, and other Brit sports cars. It is identical to the Gear Vendors unit that's being sold for 5 or 6 times the price of a used Laycock. It would be very simple to either adapt the Laycock as a bolt-on extension to the SM 420, or fabricate an input flange to make it a divorced unit mounted on crossmembers. The Laycock is hydraulically-operated, and has its own onboard pump. A simple toggle switch is used to engage/disengage it.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
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