I happen to have a PHAZER 4-stroke riser here at the moment, so I took a few measurements:
The bolt holes that run through the riser are 0.368" ( 9.37 mm ) diameter, and the bolt pattern 1.291" ( 32.79 mm ) by 2.360" ( 59.94 mm )
The hole pattern in the flange/mounting plate on the steering stem is about 0.010" ( 0.25 mm ) larger in both directions, not sure why.
The 0.368" ( 9.37 mm ) bolt hole through the riser is plenty large to allow the 8 mm bolt some movement in there,
so I doubt the slight difference in hole patterns has ever resulted in a fitment problem.
As far as I know, the PHAZER 4-stroke risers have the same bolt pattern as the larger sleds.