I've heard some people say "don't worry 'bout it, it'll do fine with the plug."
I've heard other people say "the tire is a no go now, must replace. Very dangerous."
Me, I'm more towards the former. If I thought I had 6-8K miles left on the tire, I would likely trim the plug on the inside of the tire and put a patch over it on the inside. OTOH if I thought I had 1Kmi left I would simply take the attitude "don't worry 'bout it, it'll do fine with the plug." In fact, this is what I've done on both cars and motos.
But that's just me....