Originally Posted by no1mad

Keep the Lezyne. Take the DIY route that people use to mount tail lights to rack leg struts. You'll need some electrical tape and an old inner tube.

A small section of tape goes on one end of the tube (the other to the bar/tape), to keep it from spinning. Wrap the tube around until you're just a bit larger than what you need. Then pull the tube to compress it down. Add another bit of tape to hold the tube to itself. Or depending on how much you have to shim up, you could just get by with some electrical friction tape.