On 6/6/2011, Jeff Ciampa in Warwick, NY, wrote:
"I'm looking for the rubber wheel plugs found on the original MGA 1500 steel wheels (2 each). There has always been only one on each wheel. Is that standard"?

The SPL calls for 8 pieces total, two on each wheel. I suppose it is mostly an appearance item. The only practical function would be to reduce the amount of brake dust that might get into the lug nut area within the perimeter of the small wheel cover (which is open around the edges anyway).

This has always been a bit of mystery to me. Since there is only one hole in the brake drum, and there are not four holes in the wheel, you have to be careful which way around you position the wheel during installation so you can adjust the brakes without removing the wheel. Once the wheel is in place with rubber plugs installed, it is a guessing game which rubber plug needs to be removed to adjust the brakes. So why not have only one access hole in the wheel? Even then when you insert a long screwdriver it is difficult to get it aligned with the adjuster slot. In the end it may be prudent to remove the wheel to do brake adjustments, possibly saving time as well as frustration.

In the real world I would bet that 99% of all the cars are missing these rubber plugs. I certainly would never bother to install them. If my car had them I would most likely remove them and throw them away as a matter of service convenience. I don't suppose you will ever run into a concours judge who would deduct a tenth of a point for the missing rubber plugs. Most people never know that those plugs ever existed. This has to be why the parts vendors don't sell the things. No market demand for those parts.

As a side note, I have a different theory. I suspect those two holes in the wheel are tooling holes, used to hold the part in alignment for successive stamping and forming and welding operations during manufacture. If you want to install the rubber plugs, the proper treatment wound be to never remove the plugs, but remove the wheel for brake adjustment. In that case you don't need to think about orientation of the wheel during installation.