Update: I bought the 40" MES with window from Sam's a week ago. Between weather and obligations I have only had time to season it to this point. First smoke is tomorrow with a huge butt (I do like the big butts), a couple of fattys for my son and his friends, some boudin, ABT's , and a sausage to be named later. But I digress.
My patio and deck are not covered, and I don't have a garage (carport). My outbuilding is stuffed with tillers, mowers, tools, and the like. It was getting really tiresome bear-hugging the MES all over trying to find its "spot".
Today we were at Lowe's shopping for a coat rack for the entry way to the house. We found what we wanted and then just cruised down the aisle browsing, and then a light from the heavens shown down upon a package that solved my problems. A package of four swivel casters, two with locking wheels. The stem diameter and threads seemed to be right, and you can always bring them back, so I took the plunge. We ran home and took off the stock feet and low and behold, the casters fit perfectly! They are 4" diameter, steel stem, and a 500# rating. I couldn't be happier. Best of all, the price is $19.97. I highly recommend this mod to any new MES owner. The carts are great, but for we, the economically challenged, this is the bomb. Here is the link:
http://www.lowes.com/pd_1513-80752-LO+552_0_?productId=3101539&Ntt=real organized &Ntk=i_products&pl=1¤tURL=/pl__0__s?Ntk=i_products$rpp=15$No=60$Ntt=real%20or ganized
Good luck!