Mopar W2 Econo Head 3870810

Can anybody help me find this W2 Econo Head Casting Number. I searched in vain, but haven't found any information other than this might have been the first casting of this type of head. If so has anybody used Hydraulic lifters, I was told the angle is to severe. Any info would be great. And is the bolt pattern of the Econo the same as the Normal W2's?
Thanks

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