If I wanted a Whizzum, I'd not build it on a M-600, but a M-Seven, instead. But then I'd not build it in Whizzum, but rather in Shamu... Especially since the Shamu, was designed specifically for the M-Seven. Starting with a Shamu, would eliminate ALOT of potential problems...
In fact that's exactly what I did... I took a factory Shamu in .300, rebarreled it with a M-700 take-off in 7mm Saum - Cut it to 23" - and put it into a McSwirley (Rem Mtn Rifle style) It has worked so well, I've never looked back...
GH
