Thanks for those words of wisdom
. Ha ha
Right then, Ventured out to my garage to find it covered in puddles of water from the constant rain finding its way under the old wooden side door
. The pie spokes I have are definitely not more than 2.3mm, in fact they seem a touch thinner than the 13g spokes I had made. Te nipples are definitely 4mm wide so they will fit in a mavic rim eyelet
Only problem, I think the pie spoke lengths may be a touch too short more a mavic rim ERD. The GM rim has a deep V-shaped cross section so the ERD at a guess is only 325mm. The mavics are around 335 to 338mm. This leaves a lot of excess space at either end of the spoke radius. That is around 5mm extra spoke length needed. It will be a tight fit... Lol. The spoke threads a 10mm max.
If I can get some PIE 2 motor measurements I can try and work out the spoke length suggested by a spoke calculator.