9" Model O Apron Disassembly

I have a 1928 SB 9" Model O wide-bed toolmaker's lathe with silent chain drive. I bought a book
off eBay to help me disassemble and clean my SB 9". This book covers the Model
A, B, and C, and there are some differences with the Model O which preceeded the
A, B, and C. The Model O has a nut retaining the clutch knob while the A, B, and C has
a slotted screw. The problem I am having is in removing the clutch knob (star
wheel), nut on the apron. The book states the clutch knob nut/screw has right
hand thread (turn clockwise to remove). Is this correct for the Model O also? I
do not want to break this irreplaceable part.

Lastly, I was thinking of holding the knob with a strap wrench while turning the
nut. Is this a viable solution?

Go here to see a photo of the apron and knob I am asking about.



Thank you.

The Model O clutch knob retaining nut has the standard lefty-loosey righty-tighty configuration. I found this out without breaking the shaft.