I used bolts and washers for a 3rd tier. That works fine. If you are 1/2 full of lump I have just used "normal" level for spatchcock before also. The adjustable rig is the way to go if you plan on doing more raised cooking.
No I have not, that's the reason for a smaller one in case its trash. I have a friend that has before so I'm going with what he tells me. I have not opened the fridge at all so I have no idea what it looks like now. It's been 18 days.