I changed the belt on. I changed the belt on a Eureka WhirlWind superlite, all was well but I

Question

I changed the belt on a Eureka WhirlWind superlite, all was well but I can't seem to find where this white piece of plastic approx.2" and less than 1/2" wide and there is a copper like V shaped clip, I was hoping maybe you's had a diagram or something showing where these go. Much Appreciated