i've got the silver(light up amber) 27 watt bulbs in my 323. in all four corners. i've had the back ones in for about a month now and i haven't seen a light on my screen yet. i did however for one of the oem bulbs that just burned out about a week ago. ( one of the front ones, i actually just changed those to clears w/ silver 27w bulbs an hour ago.)
so yes, the 27 watt will work fine, as far as i can tell

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