I've had these heads for years. They are correct heads for the 1971 LS6 Chevelle or Monte if they would have produced them.  They are open chamber 3994026 both dated E1071 which is May 10th 1971. They are super clean with no bad threads, corrosion in the cooling ports and have been magged and no cracks were detected. Lots of deck height left on them. I honestly don't think they have been decked and doubt they have seen much use. They are as close to nos you will find. One guide is missing. It's my understanding the 990 head replaced these and they were great flowing heads. 

Please ask questions before bidding. 

Flat rate shipping to the lower 48. 

See my other auctions as I'm cleaning out a bunch of hard to find muscle car parts.