The sleeve should have to be pressed in by a shop, you can't do it yourself that I know of. As far as suspension, +2" A-arms, +4" axle will get you wide enough to be more stable but still fit thru the trails. Upgrade your front shocks to something at least dual rate with rezzies, and upgrading the rear shock isn't a bad idea either. Understand that this will set you back a pretty large amount of cash, but well worth it. The fastest motor in the world won't help you go any faster if you can't handle the bike. A good rider on a slow bike with good suspension will be much faster than a decent rider on a bike with a big motor and bad suspension.