Oh, sorry haha I should have been more specific. I meant with text that you choose to be put on the cover.
ooh, ok..

in that case, I'm not sure. sorry

I don't think I've seen custom lettering on pickup covers before.. but theres bound to be some kind of craft suply place that sells small, precise stencils and plastics paint ..maybe
You could probably do it with vinyls or maybe stencil'd spray paint.
I'm assuming these are chrome/metal covers and not wood?
Are you talking about mounting rings or the actual covers?
Bari Build

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