I have 4 flush mount 1/2" rod holder bases for my T bar spider rigging. There are times when I would like to just put a single holder in place. I got a bunch of Driftmasters but they are all 3/8". Hate to buy 1 /2" ones when I got al these available. Anyone rigged up or found such a reducer adapter? I need to put a 3/8" thread into a 1/2" base.