The message
from Dave Plowman contains these words:

In article ,
David Holgate wrote:
But isn't this the standard way of mounting a device with a 'live' tab?

Maplin in the days when they did their own kits enclosed a Constructor's
Guide with every one, which gives clear instructions and diagrams for all
this sort of thing. If you send me your address, I'll post you one - being
a good Aberdonian I throw nothing out. ;-) It's a very useful booklet.

Thanks Dave.