Old school gasser axle kit has a 48" axle and features a 56-1/4" hub to hub measurement, wheel mounting surface to wheel mounting surface, 11" vented rotors resist heat and brake fade and have a 5 on 4-1/2" bolt pattern with 1/2"-20 studs, Features common '78-'88 GM metric calipers with a 2-1/2" bore offers easy serviceability and proven performance, New Forged 4140 steel '37-'48 Ford round back spindles provide strength and dependability for years of service, Universal design to fit multiple vehicle applications, will require welding and fabrication.