wheels/tires question

[SulphurDave]

So I'm trying to buy wheels/tires as soon as I know for sure what I need. I'm wanting the Centerline Fuel 15"x12" 5-4.5" w/ a 5" backspacing & a 15"x7" 5-5.0" w/ a 3-3/8" back spacing. Would that put the front wheels where I need them? What size tires would I need for the front? What about the back if I wanted to run some M/T Sportsman drag radials? Not exactly sure how to read their dimensions on their site. I need about a 30"-31" tall tire in the back with about a 14.5" section width. What about the M/T Sportsman S/R Radial 30''x12''x15'' LT. Do these dimensions mean 30" tall tire for a 12" wide wheel and 15" diameter? If so I wonder what the section width is.