Reset advance cam on Norton distributor

I am trying to reset the advance cam to allow best timing and the service instructions are a bit foggy on how to separate this advance unit.
heres the distributor.

here is the advance unit needing to be reset about 5º

simply inserting a 5/16 bolt for a draw bolt does not appear to be correct or functional.
special draw bolt?
thanks

There are two sets of threads in there one the hold AAU on cam tapper and another a bolt can be threaded in to tap/rap on to break the tapper loose freeing AAU to be reset. I do not have the tread sizes but by trial error I found an allen head bolt about 1.5 inch long I tightly screw in to tap/rap AAU free then kept in small bottle in tool kit along with a few other tiny special Commando tools or bits. I find it easier to use a small screw driver to hold AAU in full adv while setting trigger plate close enough to start and fine tune in cycles till everything about centered from there and timed to run well. AAU are infamous for wearing to not retard to idle down so best wishes on that function.

I don't know about that distributor type, but the newer AAU's are 5/16-24 thread for a slide hammer.

The AAU can be extracted using the tool drawn in Fig.23, p26: http://britmoto.com/manuals/Manuals/Comm_man.pdf

Thank you very much.
so this tool will do it

might fab a homemade tool , much simpler for my use.

Shop made tool for AAU removal
5/16 SAE bolt needed an oversize hole (7/32) to allow rod (3/16) to self center and not cause any alignment binding.
center punch the bolt end before drilling.
I used the tool several times with the distributor on the bike to find best timing position.

I found it easier to take a 3 1/2 inch 5/16-24 bolt and turn it down to 0.200 inch for 2 9/16 inch and put a 30 degree chamfer on the end. Easy peasy and only one piece to keep track of in the toolbox.