This is FUN, This is why I was only a mechanic !.
The "outside" of the ALLOY plate, The speedo boss is the same height, as the other bosses,
When you think about it , It was the same on Steel !,
It does not matter really, Because you have the screw adjustment on the speedo drive ?,
Within reason !! ?.
I have checked the two types of 1950 steel plates, One with speedo hole and one without,
And as we thought , The pivot boss for the shoes is the same,
I think it's 1/4", On the inside, But I find it's nearer 6 mm !!, But I don't think they did that in 1950 ?.
Once again there is slop from the split pin in the groove, And on the "A"s I think they used a screw ?,
So it does not have to be spot on, Allowing for paint etc, You can see that mine have been treated bad !,
Not me !!.
Funny when looking from above, Even I can see they are on the Piss !!,
The tricky bit is the height of the other end, The cam pivot !!,
I make it 5/32" On a STEEL plate, Vincents like these settings ??, But I am a feet and inches man !.
What ever, A 10 thou or so, Shim on the bearings outside between the bearing and the plate,
Can sort a lot out ?.
All The Best, Bill.