Cox mi 049's engine enquirey

Every time I call in on here I learn something new, even if I am an old dog,  woof woof,

As said I have acquired 4 Cox 049 engines today and they are all different, each one now freed off but in need of a good clean.

Does the 049 have a lubrication goove or channel in the crankcase main bearing, which means the prop hub and cylinder barrel has to come off to get the crank out to make sure the groove is clean and not gunged up,

and,

is there any thread lock involved with the cylinder barrel and crankcase threads please ?

The prop hub extractor, the bolt or screw to "draw off" the splined hub from the crankshaft, does that have a pin end that passes the prop screw thread and butts up against the bottom of the prop screw hole in the he crank, or is a dummy prop screw screwed into the threaded hole and the extractor screw press on that, to draw off the hub.

I know the extractor "claw" holds onto the back of the prop hub ?

I cannot see the tool on dens or other suppliers well enough to be certain.

I know about the cylinder barrel specs section, is there a similar section for glow heads and rear crankcase "covers/ carbs" please ?

Are the cylinder barrel numbers always located between exhaust ports or are they located anywhere below the exhaust ports ?

The engines I have may of course be complete mishmash of parts, I have no history of them at all.

Thanks for your help, particularly about the crank main bearing lub channel.