Belated update.  Just FYI.  First stage testing is complete and thankfully the PSRU looks perfect.  No bits of "gears" on the magnet and nothing appears wrong.   Still having grief with engine instruments and my Dynon died.  Only problem I have encountered is my flex drive with the polyurethane "Flex".  Long story short, it appeared cheap and now nasty.  So back to the dear option Vulcanised rubber at 3-4 times the cost.  Cleaning up my original coupling to send to Sydney.  Next is to adapt the prop shaft to Timken tapers, then try and destroy that.  Getting closer.  Neil.