Sorry to resurrect a ghost thread.... but I had to say something....

I just bought a pair of these for s SBC, got them assembled and on the engine. They are machined to accept both perimeter bolt valve covers and centerbolt. Aluminum perimeter covers rub the stamped steel rocker arms on the pushrod end ( I ordered 3 different sets of different brand covers, all resulted the same ). I have ordered a pair of Edelbrock Aluminum centerbolts this time and I am going to try them. They should arrive tomorrow. I will repost the results.

I will add that I am a bit disappointed in the casting and finish machining of these heads. Although you save a couple bucks, do yourself a favor and spend the tad extra for a more reputable head. I have a feeling that in the end, I will wind up having to buy 2 more heads.