[TR] TR3A Fog/Spot Lamp wiring question #2

[cfmtr3a at verizon.net]

I am mounting a pair of lights on the project.    I made notes of posts to the list over the years and thought I would be able to search the archives but 'get too many hits'.  I also thought I had a copy of Dan Master's book but I think I loaned it to someone (and not returned)

So, here are the notes I have:

Ground Relay to chassis by direct connection
Black Ground from Lamp to chassis.
fused 18g line (Red w/Blue or w/White) from Headlamp Switch to 'hot' terminal of combination fog/spot switch.   Should it be to S1 or S2? S2 appears to be live only when the headlight switch is 'on';  S1 feeds the ignition warning lamp.

Fog Lamp
??g line (Color?) from Fog side of switch to W1 on 'Fog' relay.  (I am thinking 18g)  
   options: Red w/Blue or Red w/Yellow (I think RY)
14g line (??? w/???) from A1 on Voltage Regulator to C1 on 'Fog' relay.  
   options: Brown w/Blue (same as Light feed on Voltage Regulator) or ???  (I think NU) 
14g line (Red w/Yellow) from C2 on relay to lamp

Driving Lamp
??g line (Color?) from Spot side of switch to W1 on 'Spot' relay. (again 18g?)
   options Red w/Blue or Blue w/Yellow (I think UY)
14g line (Color?) from A1 on Voltage Regulator to C1 on 'Spot' relay
   options NU or ??? (I think NU)
14g line (Blue w/Yellow) from C2 on relay to lamp
 
Questions (other than wire color & gauge)
Where should the relays be mounted?  Under dash near switch; on firewall near regulator; or near the lamp (on inner wing near horns)?
I am leaning toward at the lamp end.

If mounting one fog/one spot - is there a preferred side for either?   I am thinking about dual wiring both sides; so that lamps could be switched out as needed.  Also, that means I can run the lines down the same side and bundle/wrap the wires going to the other side on the cross-member.  

If I do run it on one side - is there any reason I couldn't run one 14g line (NU) from A1 splitting to both C1 terminals (bullet 'quad' connector)?

Suggestions/thoughts/opinions appreciated.
Also, other than British wiring - are there other sources for the specialty wire (a source that might be local).
Or, if I can't find the correct tracers...   what would be the best choices?   

Thanks
Carl
1961 TR3A TS81802LO