Silvertop - 136.14mm - 20.638mm pin
Blacktop - 140.84mm - 19.000mm pin
FRS - 137.00mm - 22.000mm pin

US (inc st170) - 139.19 - 20mm pin

Generally compression height of piston matches to the rod length so as long as you use the set it works in any of the various blocks.

Martin