I read this a few days back and the light bulb went off....I have a vibration in my gas pedal that is extremely pronounced between 1500 and 1750 RPM's and I couldn't for the life of me figure it out. (I'm slow) I have my can mounted to the brake booster bolt like many have done so I figured I would try and see if I could alleviate the vib.
I didn't want to move the can yet for no other reason than I couldn't find a good location to reuse the bracket from RX and I didn't have anything laying around to make my own so I decided I would just try and dampen the contact point between the can and the mounting bracket.
I took a small piece of 3/4 radiator hose and cut a small piece off and then cut it in half length wise 180 degrees from each other making two small pieces. Then just drilled a couple holes in each piece for the bolts (I needed longer bolts to mount the can with the extra thickness) to pass through.
I put one piece between the bolt heads and mounting bracket and the other between the mounting bracket and can itself.
I drove about 20 miles this a.m. with most of it interstate, where I felt the vibes the most, and what do ya know....Fixed! No more vibes in the pedal at all. Thank you JimmyVal for posting that, otherwise I might not have ever thought of that being the issue. Hope this helps someone.