When done correct, the tinted tails have minimal light loss. I don't see anymore than a couple of coats (tack coat and a cover coat), and a final clear coat, should be all that's needed.
I've seen a couple of F-body's going around with tinted tails and I can see their brake lights with no problems, and in the bright sun.
If I had an extra set of tail lights I'd have some tinted tails, done the right way.
I do understand what you guys are saying about the whole safety factor. There's no way I'm going to disagree about anything that doesn't put safety first.
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Bobby
Died 5/1/08, resurrected 5/15/08
ASCD SD hood, 17" Bullitts, Overkill PCM, 3.4" Pulley, NGK TR55IX, K&N 9" cone filter, JimmyC D/P, U-bend removed, Flowmaster 40 series, Hooker big bore tips with resonators, S/B brake lines, drilled/slot rotors, GMPP handling kit, KYB struts, F&R strut supports, HID's, LED's, 2.5" Air Dam, red GTP overlays on custom badges, white rear insert.