With an 11.30:1 first gear (overall ratio) and all that torque, the most significant barrier to getting the 0-60 under 6 seconds will be keeping the rear wheels from going up in smoke! (How wide are your rear tires?)

If I can get it to "hook up" decently and pin my shoulders back, though, I'll be happy with whatever time it generates.

Did you also know that the 560SEL engine has more hp and torque than the 560SL? I don't know why - the only difference I can see is that the sedan air filter has two snorkels and the roadster has only one.