The truck spindls are larger than than passenger. I don't think there's any bearing that will aloow a car spindle to fit without sacrificing strength. Perhaps you could have the spndles redrilled for the 5x4.75 pattern? I'd suggest the same on the rear, rather than adapters, especially if the truck is going to hit the track. I don't beleive that adapters are legal for use for racing, and I wouldn't trust them, seen too many failures.
