Ref the wheel cap centres, if they are like our Plus Six I think they may be a clear coat protected aluminium outer pressing glued or bonded onto a plastic backing. Mine are just starting to corrode at their outside edges. If you contact a Morgan main dealer with a photo of the centre cap I am sure they are available fairly quickly or even maybe stocked by the dealer. I think from memory they have to be gently pressed into place from the inside of the wheel, at least on our Speedster wheels they do.
Ref the wheel nuts ( bolts ), we have the same issue on our Plus Six, also the more times the wheel is taken on and off with a socket and power driver wrench the more the coating comes off the steel bolts on their hex sides. I will be ordering some more in the summer, as so far I have not located an alternative replacement. To help protect the coating on the bolts hex sides, undo and tighten the wheel bolts by hand and not use a power driver wrench.
Dave
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