Yup, I did a little series on the Maxx because I needed a break from the sky. It was a mess when I got it, but it ran great when I sold it.
When you say the "2 of the three shoes were gone on the part that screws to the gear", what shoes are you talking about? Are you talking about the clutch that mounts to the flywheel under the clutch bell? Or are you talking about the little clutches in the transmission? Maybe you are talking about the slipper shoes just behind the spur gear. Either way, let me know exactly what "shoes" you are talking about and we will go from there.
By the way, I shouldn't be answering this in here, I just can't help helping

Please make sure to post questions in the correct sections down the road.
As for the shifting, read over your manual really well before you attempt anything I'm fixing to say. It will walk you through the steps much better than I'm about to.
Are you sure it's not shifting or is it shifting so soon you don't notice it? If it doesn't shift, it will out rev the engine really quickly. If it shifts too soon, it will bog down for a while as it tries to catch it's self.
to adjust the trans shift point, there is a rubber plug on the top of the trans. You will rotate the spur gear around until you see the allen screw. clockwise will make it shift higher, counter clockwise will make it shift sooner. There is a VERY fine line where it will be perfect. It's pretty much a cat and mouse game trying to get that perfect shift. You will make a 1 hour adjustment (look at a clock, adjust 1/12 of a turn or 1 hour at a time, never more) at a time, fire up the truck and try it then repeat if it's not right. It will take a couple tanks of fuel before you get it done.
As for the shocks, I have put this on video and it will explain it much better than I can in text. Either way, welcome to the site. Can't wait to see some pics/vids of this beast (hint, hint) lol.