What's the best way to rack mount a Genz Benz Streamliner if you don't have the GB rack kit? Is it safe to just use a rack shelf and the screws from the amps feet?
I've done a number of "rack mounts" by using a rack shelf and the feet mounting holes on the bottom of the gear. Be sure the screws aren't too long and protrude up into a circuit board or something else inside the amp. If you need shorter screws you should be able to find them at most hardware stores. Take one of the screws with you. Be sure, you get metric or "American" screws the originals. Sometimes mixing these might seem to work but could damage threads or not fit tightly.
It's fine as long as the screws are not too long. IIRC, there are PCB clearance issues to be aware of on the preamp board and maybe the back of the power module.