I slightly modified the DIY mount found on this site (plexiglass and plumbers pipes) to make a pretty shallow mount.
The basic idea is simple:
-small piece of plexiglass with holes drilled in to match the mounting holes of your pj
-small screws with bolt to attach the plexiglass to the pj, the bolts rais and lower for some minor fine tunning adjustments
-a plumber floor flang attached to the plexiglass
-a plumber floor flang attached to ceiling joist (or heavy duty drywall anchors)
-a pipe nipple for the size (length) needed to go between the two floor flanges
The thing is, if with the smallest pipe nipple, I wanted shorter. So instead of metal pipe floor flange, I found the same size in plastic sprinkler pipe. I then cut to the shortest size I felt safe with. This means when screwed on the two floor flanges actually touch together.
This is a pretty low profile set up and still allows for some minor adjustments.