rear placement of Autometer gauges?

[saxmo]

I recently bought a full cluster with the Autometer monster comp gauges. The previous owner mounted them through the cluster holes and there is a large silver retainer ring (i guess that's what it's called) that protrudes about 1" from the cluster bezel. I want to somehow redo this setup to make the gauges fit flush...from the rear. Has anyone ever tackled a prob like this? Also, I did not get the sending units with the gauges...where is a good place to get those? Thanks for the help... Also, I do have another tach bezel that I can use to mount the gauges...