sounds awesome ...at busco last time i tried a test with just the center tires driving my half tracks ( removed the rear chains ) it worked great at home .. more power and turned easier . but the mud at busco was real sloppy and the center tires just spun in the tracks . so both rear wheels driving is better . highboy still works great ..the design has been proven to work well . may get adair to make me a set of half tracks though . homebuilts have taken a beating !! keep at your projects and have fun . jboy