Just as a side note, as someone mentioned, LR did make a tapered stud to be used w.o the sleeves in the late 1990's
I complained about mine rusting on my 1997 in 1999, and the dealer replaced them with tapered one which no longer used a sleeve.
Worked much better, but still rusted.
Jtek? ( gulfcoastrovers.com) http://www.gulfcoastrovers.com/pages/products.asp?uid=7
made these and is what I have used for years.
Not completely round which helps to hold the windows in place I think