LarryD:
Mounting your PCBS etc. to the inside of an encloser without drilling through your case.
See the attached image:
Use double sided foam tape or epoxy glue on each foot (sand PCB prior to adding glue to it).
Consider self sticking Velcro.
When I want to mount a project inside a box without holes, I use an acrylic (Plexiglas) plate slightly smaller than the inside of the box.
All the holes, standoffs, etc... are mounted to the plate. Then the finished product is "glued" into the project box with double sided foam tape. Works like a charm.