Yes the center cap would have holes that line up inbetween the spokes and the wheel holes would be threaded. ie the caps have screws that hold them on. Also the center hole would be larger on the real empi's.
like this
http://cgi.ebay.com/ebaymotors/ws/eBayISAP...em=220376544857Still they are desireable wheels for some people me included. I always need wheels for bugs.
I bought some like that at super shops in the 80's I think they were american eagle maybe. They take a 2 inch center cap. It's usually plastic and you can find them on ebay usually. Also you can get a billet cap that is held on with internal set screws on the inside. The short center caps look the best but will need to clear the hub and axle nut.
If you take the time those will probably polish up real nice. You can get polishing stuff good enough to do those at harbor freight. Do them while the tires are off so you can get any nicks on the rim sanded out. I use wet or dry 400, 1000, and 2000 grit paper to finish before polishing. A air tool with a 2 inch scotch brite pad is also a easy way to start on the nicks. Aluminum is almost as soft as bodyfiller to sand and cleanup.
Of course the real empi's were the best probably but those look to be well made for copyies. I have seen rougher copies.
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What he said. . .