flywheel removal, what size socket? reploarization

[portuncia]

My B-112 project continues. Found out my tractor has a magentron but I don't think the flywheel was reploarized. Two different Briggs guys told me some run fine without it. Mine ran strong but idled a little rough, Briggs said it was likely more a valve clearance issue. Now I need to decide whether to send the flywheel in while I have it apart. Does anyone know the size deep socket or wrench needed on the nut? I have done alot of reading on the subject using the search function, has anyone else here had experience with the magnetron conversion and not repolarizing their flywheel, did it have power but idle rough, not run at all etc? Thanks for the help. Jeff