We have a set of 862 cylinder heads for our LM7 5.3 liter that needed TLC. Our new cam came with a set of Trick Flow dual valve springs, locks, retainers, locators, and seals. We also pulled the valves and cleaned them with some throttle body cleaner and a bit of red scotchbrite in a drill. This method is fast, easy, and when you use scotchbrite, there is very little risk of valve damage. We verified the valve stem didn't change at all with a set oc calipers.
Note: We didn't have the head sitting on a towel or wood plank, we did this video, and then took it all apart again for to prep the gasket surfaces and the a deep clean with in the parts washer. In hindsight, we should have used a towel for the video.
Before reassembly, we lapped the valves with some fine lapping compound and show you a trick to get the valves lapped in quickly. We don't need a valve job, as the valve seats lapped in nice and smooth, not pits or divots in the seat where it can leak.
Then we clean the head and assemble it.