I bought two cases for our kitchen and I like them. The blum is slightly smoother but at 3x the cost I'll stick with the csh ones.
These measurements are for 1/2" ply.....
OK my jig for the rear hole puts the hole .75 from the side and 7/8 from the bottom. It's a simple jig. Just two pieces with a Dado and a piece of 1/4 ply. Run the Dado down the center so your jig works on both sides of the drawer just by flipping it over. With thicker sides the distance will change.
The rear notch is simple. Using a oscillating tool cut the back of the drawer flush with the inside of the side. Then measure over a little wider than the slide iirc 1.25 and make another vertical cut.
Then go flat against the bottom and take that chunk out.
When done it looks like this.
Now back to the width. I couldn't find my notes but... Drawer width is dependent on the width of the drawer slides. You don't care what the box size is.
Pull the slides out a little and measure from outside to outside. This is your drawer interior size. Add the thickness of your two sides and that will be the outside dimension of your drawer box.
Then make your drawer depth slightly shorter than the slides are made for as this makes drawer install easier.
Really should do a step by step with pics but I don't have the time. If I confused you etc shoot me a pm and I'll give you my number as its easier to explain over the phone or actually seeing it...
Ignore the sloppy drawer I the pic. That was a test drawer. Also I was going between staining the doors for the kitchen this post and selling an item I had on craigslist so nothing is in order...