I only have the older version with two holes (and no metal reinforcement in the axle), and the holes are concentric with 32000/602.
http://www.peeron.com/scans/8700-1/1 shows that the electric switch can be used directly with the 3-hole Version:
1 16 0 64 80 -1 0 0 0 1 0 0 0 -1 73261.dat
(I can align mine that way, but not connect them because of the pin at the switch).
And the holes at the outside of the switch (for the plugs) are all 3mm (same as the pins) --> 3.5 LDU radius
http://www.peeron.com/scans/8700-1/1 shows that the electric switch can be used directly with the 3-hole Version:
1 16 0 64 80 -1 0 0 0 1 0 0 0 -1 73261.dat
(I can align mine that way, but not connect them because of the pin at the switch).
And the holes at the outside of the switch (for the plugs) are all 3mm (same as the pins) --> 3.5 LDU radius