My little 882 was hammered pretty good when I got it. I had to replace the bearings in my cooling fan also. Not that hard of a job but I didn't note what gearings it took.

Here is what mine looked like.
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My steering column was in bad shape too. Cleaned it up good and put red Loctite on it and hammered the tube back in and never had another problem out of it.
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You can take the slop out of the box if you pull the cam follower out, put it in a drill press and touch it up with a 4" side grinder. They get a flat spot on them from the wear. You also may want to check with Jeff in PA if you need a new one. Here is what mine looked like before I cleaned it up.
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How much play is in the drive shaft when you grab it? I'm thinking a worn driveline caused the issue with the pump. Check the rear coupler for wear. Mr. Jeff in PA can fix you up there too.
FrankF3 found a replacement for the idler pulley if I can find the post.
Keep us posted on your progress and congrats on a great little GT.