Early W111 Bleeder Screw Size/Pitch and Single Circuit Master Cylinders...

[fritzintn]

A few short questions before I run make the rounds at the local parts stores:

The car: 1962 W111 220S sedan

- I'd like to replace my bleeder screws with 'Speed Bleeders' - as connecting the Motiv pressure bleeder didn't go so well. But I need to know the thread size and pitch....

- Secondly I have the older single circuit, non-boosted master cylinder. It doesn't appear there are any rebuild kits - and the new units all appear to be for the boosted dual circuit units.

I'd like to move to the dual circuit unit (and understand I'll need to replumb the lines) - will it bolt up to the firewall/linkage? Can I keep it non-boosted?