I've just done my first traffic signal restoration (not including a neon ped signal which is still neonless).
I have three old AWA signals, which are basically the same as the UK Plessey 'tin' signals. With some unseasonably warm sunny winter weather recently, I decided to strip one down and respray it.
Here's what I started with.

The one on the left had a hinge and a door clasp missing, so I decided it would be done first.

Stripping it didn't take long (these are very simple signals). I pinched a 'spare' hinge from a cut-down signal that I was using to provide parts for several other projects.

As I intended to repaint this signal in the 1960s all-over yellow that was used in Melbourne, I gave it a coat of white primer as spraying yellow over black was unlikely to work too well.

http://a2.sphotos.ak.fbcdn.net/hphotos-ak-snc6/185449_10150257920482286_657347285_7744004_7725990_n.jpg
http://a8.sphotos.ak.fbcdn.net/hphotos-ak-snc6/185449_10150257920487286_657347285_7744005_4299680_n.jpg
And then came the yellow paint (click on the links above, because they're horizontal pics, considered too wide to use here).
http://a4.sphotos.ak.fbcdn.net/hphotos-ak-snc6/185449_10150257920497286_657347285_7744007_1128715_n.jpg
One of the hazards of using bright colours outside on nice warm days.

He eventually worked out that there was no nectar or pollen to be found here.
http://a6.sphotos.ak.fbcdn.net/hphotos-ak-snc6/262849_10150258602397286_657347285_7751864_3841916_n.jpg
The reflectors reinstalled.

And finally, the completed signal. Well, okay. Still no visors or wiring. The wiring will be done soon. Visors shall have to wait until I can get some copied from two that I have.

I thought it came up rather good for a first effort. I have two more of these that I intend to restore to a 1950s striped black / yellow / black. One of them shows the signs that it had originally been painted that way...

You can just make out the line above the amber lens in the above image.
Unfortunately the winter weather returned today, so no more painting for a while.
Darren.