Regina ORO the last 2 are left hand threaded there is a shoulder in the body they stop against.

clean it up and Look between the cogs for the shoulder if there is a spacer then its not , shoulder in the far inside may be splined stages .

ARIS there's 2 bigger over the body thread and pawls and ratchets, smaller as the tooth count has to be smaller..

A Cheater Handle became Part of my chain whips so they're a bit over 2 feet long..

and To cure Blow outs there is an 1/8" spring clip masterlink wher the chain meets the rather thick piece of Hot rolled steel

with the Holes in the edge the ability to hold the Body steady while the 2 chain whips are Pulled against each Other will help A Lot..
It aint watch repair, some brute force may be needed, after all the hill climbing of past decades has tightened it Up.