OK so, this morning I scribed horizontal lines through the driving axle centres:
Generally mark on the inside of the chassis frames, not the outsides which would be visible to the public. The whole point of doing the lines is to have a visible guide to where the axles should rest once the suspension system has been introduced:
I will need to scribe yet more lines to take account of where the leaf springs will run, and where the fulcrum points should be (midway between the driving axles, for example).
Since this particular kit was produced before Ireland changed over to the Euro, I had expected bits to be missing. In fact the only things that were absent were dedicated wider spacers for 21mm gauge builders. Not sure if "Weshty" / Des has been able to supply wider ones since taking over the SSM range, but they certainly wouldn't go amiss. For my part, I'm making my own. The first major part is the upper rubbing plate which sits above the bogie, which you see here at the top left corner of the fret:
As designed, it's for 16.5mm gauge only. I need to make a wider replica of it, keeping the same overall length and fold lines for now. In order to end up with an overall chassis width of 17 to 17.5mm wide, the estimate is that the spacers should be at least 16.7mm wide.