How to DCC Fit Old OO/HO Gauge Locomotives!

Okay folks, Here is a how to on
fitting DCC decoders to none DCC Ready locos and locomotives.
You can DCC Old Hornby, Tri-Ang, Bachmann, Lima etc in the same way.
Just taking care and being a bit methodical will result in n your loco being usable on your DCC layout.
This Jinty for example picks up power from the chassis on one side and Not pick ups like modern stock does, so we have to take a few extra steps to get things working.
Also pay particular attention to magnets and weights within the body, as these shifting about will likely cause short circuits!