If you can wait Mark I will walk you trough it when I have parts in hand.
If you want to try, know this, there is a tapered hole in the center of the wheel. When you tighten the nut on the tapered wheel collet it is forced to close down and grip the axle. Its a great design, until it jams. But it grips well and its the best way to keep axle and wheel running true to each other.
Step 1- back the nut off,just half a turn . step 2 tap the nut towards the wheel to release. Alternatively you can tap the wheel towards the nut if nut is well supported.
Its like any collet they can get jammed. But a tap of the nut in the correct direction (towards the wheel) and bit of WD40 would not be a bad thing as well. The trick really is finding a tool that will get in there to take the first wheel off. A small vise with a small wrench will support the first (loosened)nut then you can tap on the outside of the wheel with a flat plate so as not to damage the face of the wheel.
This is easy once you have done it. Hope this is not too confusing. I will send some pics if you are not sure.
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