shamu --=--
Some of these I'm sure you already know, but that said, you asked for it!
1.) Make sure to have a really good quality 'C' clip removal tool. If not, it's a real PITA as the not-so-good ones slip off constantly and mark up the large aluminum block. By the way, those clips will rotate if they are not frozen in place for a better grabbing area.
2.) If using metal picks to remove the old O-Ring's, don't dig them out too aggressively as you will scar the inside of the cylinder and the O-Rings will no longer seal due to the scratches.
3.) Be sure to replace the O-Rings on the check valves.
4.) Stabilize the Box on your workbench by placing something about the same height as the motor (this with the front of the Box facing upward). This makes life a lot easier without struggling to keep it from flopping around.
5.) Once you have removed all of the 'dirty' stuff, before replacing parts, wash your hands or use latex gloves for cleanliness.
6.) DO NOT LOSE the black spacers that are attached to the stainless-steel tubing.
7.) You shouldn't need to remove the pistons; they can stay in place as the cylinders can be pulled through the aluminum block (sometimes they are stuck though).
8.) If using Teflon Tape for the air line threads, DO NOT run it up to the tip of the starter threads. It will peel off and stick inside the lines.
9.) If you can't get enough flex out of the tubing to pull out of the cylinder threads, you may need to remove the air lines from the aluminum block to do so. This means that you need to replace the upper cylinder before the lower to allow reassembly as the aluminum block with the lower cylinder in place creates a non-accessible situation to tighten the upper air line connecting to the aluminum block.
10.) Once disassembled, things are gonna need a lotta clean-up,, especially inside.
That's about it. It is actually very easy to do and the video that you have already looked at is still a good guide.
mike