A very versatile street rod style bracket system. Works well with most induction systems. Will clear multiple carbs, fuel injection, etc. Bolts to the head and top water pump bolt holes. The alternator bracket will fit all 1969 and newer heads. The A.C. Compressor bracket fits all G.M aluminum heads including the fast-burn aluminum heads and may be used on 1969 thru 1986 cast iron heads by drilling and tapping one hole for the upper mounting point. Will clear up to 3 in. tall center bolt valve covers when used on 1987 and later heads. Will clear up to 3 3/4 in. tall valve covers when used on 1986 and earlier heads.