Working on an older 60" mower. I'm guessing its a model 31229. The center spindle was complete toast. I was able after a couple months to find replacement parts that did not drain my bank account. How are the bearings set or pre-loaded? The OM states the blades have a torque. I can think the outer spindles could be adjusted by the top nut. But what about the center spindle with the thin head bolt? I see no shims in the IPL, I can't imagine the bolt is just tightened and the pre-load is correct. Also the lift assist springs are missing. I'm guessing they are different than the ones used with the 50" deck or lift assist by the different part# Is there a way to ID the springs? Length, # of coils ect.