I replaced mine with size "412" rubber stems. They are really short, about 3/4-7/8" and I got them at NAPA and the mom&pop shop where I bought the tires put them in for me. Technically illegal for them to do that, so some shops may not do it.
Lake Tahoe Hi-Lo's
S. Lake Tahoe, CA
08 Wrangler X 4dr. 6sp: Winched, bumpered, Atlased, 5:13 Rubi axles, 37" Kevlar MTRs, Treks skids.
87 Toy BJ70 LandCruiser. Winched, bumpered, 35ed, locked, slidered, dieseled.
87 Toy 4r. Winched, bumpered, dual cased, 35ed, locked, slidered. -Sold, to pay for Jeep parts!