340 T/A (U code) head value? (Pics)

As far as I know there are specific W2 (&5) rocker shafts and rockers that go with them. This is in there offset and rocker body dimensions. Length of top from the fulcrum points center. (And others as well.)

MP uses/used Crane for this as you may know. The best set ups are from Crower and TD, which is often mentioned by name from MP.

Yellowrose has more information on this and there issues.