Your wheels look like they require a shank nut, NOT a taper nut. Agree with LF. Also, be advised that there are two tapers, 60 and 90 degree. I got Bassett race wheels that require 90 degree taper nuts. 60 degree will not stay tightened on a 90 degree wheel.
And what ever you do, do not put washers behind them.
Summit Racing has the correct shank nuts in Pantera thread in various lengths.
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