A 150/90/15 will fit without the fenders and chain guard. That's the smallest 15" tire available with wide white walls. I'm pretty sure there isn't an 18" tire with www that will fit the front. Mother Road Customs makes good quality leather solo seats, Mother Road Customs. You need a seat and a mounting kit, LaRosa makes a mounting kit that will work on your Rebel. Zombie Performance makes great quality handlebars but I'd have them make something a little more interesting then drag bars.