There should be a raised section in the swing arm that holds that end of the pin and stops it turning when you do the short bolt up on the other end. That probably got rounded off and the weld was to stop it turning.
If you find that you do have to replace the swing arm then it might be worth considering replacing it with the lighter aluminium swing arm from the OE. You would need the longer OE axle bolt to go with it though.
Bolt is out without too much butchery - can anyone recommend bush ETC kit ? its a 1994 4gy metal tank 250 raid
I've heard all balls mentioned an Wemoto also do kit called Slinky just bit concerned about right kit for this model
Cheers