From what I was finding when researching the valve cover leak issue, it appeared that there was a redesign of the valve cover to remedy the leak. We’ll see. It was relatively inexpensive so I figured why not.
So about the AFM disable, what’s the best way to do that? A Range device? Any oil catch cans you’d recommend?
The valve cover redesign was not to reduce or remedy a leak, it was to the PCV baffle to reduce oil consumption. There's an inlet hole in the baffle that was ill-placed. It allowed the splashing and/or squirting oil from the rocker arm to go into the hole where it was more easily sucked up into the PCV hose and, ultimately, into the intake manifold. The new cover has this hole relocated. IIRC, all 2010+ got the redesigned cover at the factory, so your '12 should have it.
The good news is that it's not money totally wasted since there are plenty on here that have the older cover and would likely buy it off of you. I bought one for my '08 then found mine had already been changed so I sold it.
The Range is the
easiest since it's a simple plug-in device, but it's $200 new. I see them for sale on the forums for $100-$150. I think having it tuned out is best since I wouldn't want this device sticking out from under the dash all the time (it's not much, but still). Plus, there are reports that it can drain your battery if you leave your vehicle parked for extended periods. I don't wanna have to remember to unplug anything like this if I were to park for a while. There's a guy that will turn it off with a tune for $50 (Info here:
https://lt1swap.com/afm_delete.htm), but you have to ship him your PCM. If you can wait a few days, this would be the cheapest route for tuning. You can pay for expedited shipping if that still makes it worth it. You could check with your local speed shops to see if they will do it. It's a very straightforward process so any shop worth a crap can do it. I had one near me turn off AFM as well remove the speed limiter and rear (after cat/"downstream") O2 sensors from the tune for $150. No power tuning. The most expensive option would be to get a full custom tune, such as that from Black Bear. Turning off AFM would be the least of the benefits with this. The cleaned up transmission shift tables and other tweaks would make it drive so much better and prolong the life of the trans from the reduced slipping and less gear-hunting.