Need some advice on material selection

[astroracer]

Okay guys, sounds like I have a plan.
John U.,
The stackup over the inner sleeve is exactly as you mentioned. I have yet to check it with torqued fasteners in an installed position but I'll do that as soon as I have some brackets made. I will then build my welding fixture to suit.
I think I will use hardened washers on the inside of the brackets and plug weld them from the outside through holes drilled in the bracket. I can then finish off the welds to make them disappear. 7ga 1018 will be used for the brackets.
Ruggles,
The bushings have grease grooves and I will be adding grease zerks to all of the bushings after they are welded up.
Thanks to everyone who has jumped in to help. If anyone see's any problems with this plan please let me know your concerns.
Mark