[Nexus 6P General] RngrYogi:
Ok I did several versions of this mod myself and the Op's decision to change to a thermal pad was a great idea as I had decided to do this from the beginning after seeing the gap between the lid and the chip. I removed and reattached the camera's glass cover and the plastic cover at the bottom many times and must say using the correct amount of heat and being careful resulted in no damage at all to the pieces. Using a X-tronic #4040 and applying 150c for the glass and letting the heat soak in a little allowed me to remove it with no bending at all. 100c on the thin plastic at the bottom resulted in the same results. A couple of small nicks at the injection site of the metal razor blade to the frame itself were unavoidable especially after multiple removals but if that is an issue you can always buy another back and glass as they are on the market now or find a seriously thin plastic razor which you can buy.

I testing using a 1.0mm soft pad I had extracted from a AMD 7970's VRM rail and sink. Obviously it is not a good idea to reuse a thermal pad but I know that and just wanted to test pressures, gaps, and softness of the pad and to see if it helped. It did. The 1.0mm pad was a bit too thick but this pad was super soft and allowed a little more pressure after it was squashed by the plate and the board after being screwed back to the frame which was ok considering the pad will fill the gap well and still did not cause a deformation or extra pressure on the motherboard after reseating it. I also used some cheaper thermal paste to do the outside. ThermalTake TG-7 which as I found out later only had a thermal conductivity of 3.3W/m-K so that was not too good considering we are dealing with low pressure, largely imperfect surfaces, large gaps, and lack of a good true heatsink.

So the device transmitted heat a little better and still throttled a lot showing how much heat was still being insulated inside the chip. So after testing I ordered some FujiPoly Ultra Extreme 17W/m-K pads from Amazon and some good Gelid GC Extreme that has a from Amazon also. The pads are only .5mm thick like the AlphaCool in the OP and are much more stiff and somewhat brittle to bending and excessive movement compared to my previous pad from the 7970's VRM sink, so be careful with them but the stiffness assists here. The Fujipoly pads came with the exact same protective covering as the AlphaCool Pads so with the similarities in look and specs they should be almost exactly the same. I used the pea method to apply and spread the TIM when dropping the motherboard down to be reseated. The amount used was more like a squished grain of rice as I did not want to insulate the chip instead of transferring the heat to the frame.

After redoing the mod with some quality materials, benefits are realized, and I could not be happier. Upon some tests using geekbench and a few games monitoring the cpu temp and throttling habits I can attest to the fact that the chip and thermal solution here definitely wicks the heat away from the chip much quicker than the stock solution. Now that being said this chip still throttles like a boxer with no corner or water but what I saw was how quickly the chip, software, and hardware throttles in place relieved themselves after the severe stress was gone allowing the phone to turn the cores back on and turn up the Mhz again. You can experience the front glass, frame and the rear casing heating up quickly under a moderate load and thus becoming heat soaked pretty quickly. This may result in more dangerous heat levels reaching the user's face on a phone call so just be aware and don't scare yourself or drop your phone. This mod is only meant to be attempted by experienced techs and thus they accept their own responsibility doing it. The cost of these TIMs were around $48 Shipped overnight from amazon. So pretty expensive, but they give good results.

My tests included multiple runs of geekbench which saw scores dip into the low 2500's after 3 runs on stock and taking a good 5 or 6 mins to recover from all forms of throttling. After the mod I could not get my score to dip below the 3800's and was consistently staying in the 4000 range after the 3rd to 5th runs. Upon checking how quickly the chip recovered from the throttling was startling! As fast as I could switch to Kernel Adiutor after a 3 run test and then a 5 run test the device had dropped almost instantly back to around an average of 45c and saw the cores reactivate and the Mhz restrictions lift within 5 seconds of switching, all while the body and frame were totally heat soaked.

I am currently running the Dirty Unicorns ROM.

All in all this mod definitely helped my phone's performance and longevity and I must give props to the Op on attempting to open this beast and take on the task of doing what everyone here at XDA strives for and that is pushing our already ridiculous devices to the extreme and allowing us to squeeze every drop of performance from them. My many thanks on putting this out there and giving us room to play. Because I totally understand how difficult it can be to read some the the replies you can receive after doing something like this to a flagship device. I agree that the process needed a little refinement but I also must say the title of this post gives the intended results. :highfive: