Holo Audio May / please help

I have a set of RevOpod footers that I would like to move to my Holo Audo May DAC.  The footers are said to work best when the OEM footers are removed and replaced  with the RevOpods, screwed directly into the the bottom if the DAC chassis. 

I began the footer swap process, taking out the screw in the bottom of the OEM Holo footer but the old footers were still stuck fast even after removing the screw in the bottom of the footer.  Strange.

My question is:  Has anyone has experience with this? Are the OEM footers glued/adhered to the bottom of the chassis or perhaps are the footers secondarily screwed fast from the inside of the chassis making them unremovable from the outside?

Thanks in advance,

Rick