Randy, you might give Energy Suspensions bushing grease a try and see if that helps keep the noise down on the teflon bushings. No affiliation.
I considered the drilling out technique but wanted urethane, not stock rubber material. Did not know where you could source stock configuration urethane bushings of any size ID.
I was wary of drilling out anything on the same center-line as the stock ones anyway. It seemed to me that would remove too much material and put the larger bar in contact with the little retaining lip on each of the stock mounting clips. Plus, having a very smooth hole in a bushing that started life as a 1 inch hole bushing appealed to me. Do not think my drilling could replicate that. Anyway, this is why I did the trimming as I described. It results in less material at the top curved part of the bushing and leaves enough material at the bottom flat side for the bar to clear the clip retaining edge. Apparently you did not encounter such a problem. Perhaps you did not use stock mounting clips like I did. Or maybe, my measuring was off.
Anyway, not to worry about doing any of that now that Buck has identified a source. Thanks Buck!
BTW, I do have the stock mounting clips wrapped with reinforcing clamps.
Gene