Nick,
Some of this is in the documentation, no?
I am incredibly pushed for time at present; head gasket just broke on my car, dammit, and a trip to South Australia tomorrow, but Rom's suggestion is really good, works well. Photocopy, on a quality machine with non-distorting optics, or a scanner (place right in the centre of the scan range) or even take up the pcb and measure it off with an accurate caliper.
I don't have the figures off hand, but I can tell you c to c distance between the tubes is 70.4mm.
Cheers,
Hugh