These were made for a metal CP (I think? these were the midnight resistance sticks, right?)
So the best way to mount them is through a metal panel, obviously.
For your MDF panel you could cut a hole large enough to fit the entire stick through in the panel then cut a square of metal larger than the hole i nthe MDF and mount the stick into the metal. then you could route out around the sides of the hole of your MDF to the depth of the metal and glue it in place. Incredably labor intensive but it will look nice when you're done