Help with bigger tires

[PuddinXD]

Hi everyone, 

First off if there is a more appropriate place to post this please let me know and I'll be happy to repost!

So to start off I have a 2015 Sierra 1500 with spacers on the top of the shock tower that create about 2-2.5" of lift and 3" rear blocks. I searched over multiple forums but couldn't find anyone with this exact issue. I went from stock 265/70r17 bridgestone duelers to 285/70/r17 Falken Wildpeak AT3Ws. Everywhere I searched it seems that plenty of people run the 285/70/17 KO2s with no issues with a level so I figured these would be the same, unfortunately at full lock the tire rubs on the UCAs. I was wondering what my options here are, the way I see it I have 3 options.

1. Downsize to 275/70/17 AT3Ws and get a little money back

2. Put some spacers on and hope that the UCA rub goes away and doesn't create a problem with the fender liner (I don't know much about these or how far I would have to go with them, I would prefer not to cut anything)

3. An offroad shop said that they could shave down the UCAs if they're the right material (I forget what kind I would need to have, I know that there are 3 different stock options for 2015).

 

Any comments or suggestions would be appreciated! I have 30 days with the tire shop to decide what I would like to do, but I would prefer to get it done sooner so that I can stop worrying about it! Thanks everyone.