The last year of the integral head was the last year of the 250. I don't think the 292 ever used that abortion. Unless it's been changed, an 82 250 will have that POS on top of it. Get an early head and manifold set (pre-75 or so) from a boneyard and go from there.
Santucci's Inline 6 Power Manual has all the info on the L22 engines that you could ever need.
