Yes, Squealing Pig. I meant the way instruments are either inserted from the front with the bezel proud of the panel, or from the back with the glass flush with the panel.
One reason I was asking this question is that it seems to be a national thing.
In the UK, instruments are normally rear-mounted. The French, Russians and maybe others have also favoured this method for many years.
On the other hand, Americans (always best for easier maintenance) used front-mounted instruments. The German Luftwaffe of WWII was the same. Cockpit clutter increased a lot - just take a look at US fighter cockpits from the 50s and 60s!
Yes, it was a pain fitting rear-mounted instruments but hinge-down panels eased that problem!Brine