D4B and LD4B side by side pics

Around 1975 I had a 1964 273 with the manifold bolts at more of a srtight down angle.

I wanted to put a Wieand single plane on it to replace the factory iron single plane.

My machine shop just milled the holes in the Weiand a bit wider and then milled a 12 inch piece of aluminum flat bar at the same taper angle to close the mismatch bolt head gap to the early 273 heads.

We then drilled the 10 holes and cut 1 inch wide tapered shims. Alowed me to bolt the manifold on without making it worthless for a later 340.