When fitting a disc brake to a PK steering column in combination with a PX shock absorber you require a shock absorber base plate that is offset by 8mm. If a PK shock absorber is used then a shock absorber base plate that is offset by 4mm is required. Both combinations are very popular when upgrading the V50-125/PV/ET3 and the GTR/TS/Sprint/Rally with a conversion fork.
With an extreme conversion to 12" in addition to the conversion kit and a PX shock absorber, a shock absorber anchor plate offset by 16mm is also required as the steering column is re-welded/re-aligned. This means the wheel contact patch is once again in line with the rear.