I just realized what I told you is only partly true
I have no cats so I had to have my O2's tuned out. You might be alright since you're putting in the high flow cats. But there is still a chance that the O2's might turn on a CEL with the HF cats. But you wont know till you try, every truck is going to respond different.
There is also the option on the non fouler trick if you wanted to try that too.