I have found that while it is good to polish the TB where it rubs on the frame, it is not as critical as polishing the rear of the TB per instructions found on the site and the slope down at the rear. Also, while the CGW rollers are great kit, most I've found are too large for my guns and contribute to stacking.
While the P series are great guns, the gritty stacking triggers are the low point of the breed. If you are lucky you can find the one you want that is not - they DO exist. Most need plenty of work. Sure, lightening the crap out of the mainspring makes all feel much better, but I want a gun to also be able to bust hard primers.