The studs you highlighted aren't for mounting wheels. They're part of the brake drum attaching hardware on the wheel mounting spider. There are tubeless open center rims that will replace the tube type wheels you have now, but they're pretty spendy.
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
Love your enemies and drive 'em nuts!