On my first uds I put in four racks for doing ribs. I used 1 inch bolts as I was worried about getting in and out with the other racks. with such short bolts you have to be very careful to center the rack on the bolts so it doesn't tip. On the next 2 I used 1/1/4 inch bolts. when taking a rack up or down levels you may have to tip it slightly to bypass the bolts. use caution because if you tip it with the grate bars instead of against them the meat can slide and you could potentially drop it off the grates. trust me about this one, once you have a butt up against the wall of the drum with the weight to the edge it is difficult to recover. As stated by others get good gloves and dedicate them to smoking. have a place to set your racks and pull the whole rack instead of individual meats and get the lid back on as soon as possible.
2 Primo XL's, 3 (not very) Ugly Drums, 1Ugly Drum, 2 22.5 wsm's, and 2 18.5 wsm's.