I believe those rivets are 1/4" diameter. If so, the hole in the hub flange once the rivet is knocked out is just right for a 5/16-18 tap. Tap the holes, use a countersink to bevel the hole in the drum, and attach the drum to the hub with short flat head screws. Yes, the lug bolts will hold everything together OK if you choose not to bolt the drums on.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
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