I'm in the middle of my first upholstery project. Also in the middle of building some equipment that will be used in a current business venture (Wright venture 1002...in Fusco terms). This piece will host a lcd screen and mini computer along with a few other pieces of media equipment. It's my first time using speaker carpet to cover a case. I'd have caught some pics of the hands, but they were covered in 3M 77 spray, fuzzy black fibers and wasn't touching my phone; luckily they peeled clean nicely. The cabinet is made of 1/2" plywood with 3/4" MDF top and bottom.
Anyhow I found a great place for the road case hardware (speaker carpet, steel corners, latches, etc.), Reliable Hardware, nice folks to do business with. Here is how it turned out so far. I sprayed the 3M 77 on both the case and carpet, let them dry some to finish trimming out. Once the adhesive dried some, you could lay one piece of the carpet over the other and cut through both for a matching seam. Just peal back the top layer and put out the scrap from underneath. There's not really any grain in the carpet, so both sides of the seam butt together nicely without a noticeable seam.
There's definitely a method to the madness, a little practice and this should be pretty easy if I need to do more of them, but it turned out pretty good overall.