Aaron:
I took your suggestion and simply carried the grinder up from the work bench, sat it on the shelf on the small ladder and ground the lip off:

Sorry about the busy pizza box, it's all I had lying around at the time. I then filed and painted the area where I grinded.
Next, when I put it all back together, I noticed the radiator seemed to move a lot with the new mounts. I called Grover... errr... Eric to give him a hard time because... well... it's my mission in life

and he suggested wrapping the posts with electrical tape. I looked at this idea but deemed it unacceptable. So I found some old Hose Techniques silicone hose pieces I had laying around and used those:

Worked great... The trick is to use some dishwashing liquid to slide them through the rubber grommets.
It would have all been perfect had I not scratched the heck out the cover trying to clean the back...
Oh well. GS-27 worked pretty well for now.
Hope this helps.
Best,
SJ