Putting a new face on old AD gauges

[GeorgeLeonard]

I bought a pair of old AD gauges today to try to figure out how they come apart to put new overlay type dials on them. They dont appear to be easily disassembled. In fact, they are assembled and then crimped to hold them together. The only thing I can figure out is to stick a small screwdriver in there and carefully try to pry them apart. Does anyone have a better idea because I just know Im going to break these by trying?