Aye Steve,
Forgot to mention the DynoJet kits for the SRX600 standard carbs so here is a link:
pdq1_DynoJet_SRX600_carb_kitGo to DynoJet for other suppliers, I have used the kit and it works well, but cannot tell you where it came from!

Suspect the problems that CrazyFrog has had with NRP are due to them including 'rubber' 'O'-rings, rather than Viton 'O'-rings.
Here is the link to DuPont, whom manufacture Viton:
DuPont_Viton_O-rings_FAQ Yet again, cutting corners and substituting cheap Chinese rubber 'O'-rings for Viton 'O'-rings is easy and makes a large difference to the suppliers "margin"! But it could be your neck!

My regards, Bill