Mine uses all stock threaded mounting points. I started with a light framework made of .75" x 1.5" (1" x 2" in US) fir (pine), then countersunk the fasteners (stainless cap screws) so the heads were flush.
The two front mounts are near the stock speaker location. (on the floor)
Then cut a base of .25" plywood, & built up from there.
LOTS of glue, screws, & finish nails is key when building light...![]()