I started by drilling the lower hole as this was the easiest with no edge distance issues and it also can be used to secure the VS better as clamps could not reach that low.
The two through the bracket was next. I started with #30 and measured, right on the money 3/8. I upsized to 3/16 and measured again, 9/32 from the edge to the bolt, which translates to 3/8.
Phew, I am glad that one is over. I still wonder why Van's makes it 3/8 when 1/4 actually should have 1/2. According to answers given to other builders, any edge distance is acceptable. It makes sense as the loading is from the below (tail wheel pushed up) and it is plenty of material on the loading side.
