I bought a second hand classic and have just done my MOD1 too. I have the webbing and clips on them so they clip together. Nice enough idea, but one more thing to remember when getting back into the boat!
One idea I had was to take the webbing straps off them - put clips on - and clip the slave off on a D-ring RHS of chest. The master would be clipped to a piece of bungee on the LHS of chest so I could check that regularly - then just unclip the slave less regularly and compare....
Yes Roy, this is exactly how I wear my handsets. I wear them clipped on coiled bungee each side so when I am diving they hang down on the bungee. When getting back on the boat I clip them back up so they are stowed away safely.
Have a look at my profile pic.