RHD Brake Light Switch - Where to Place / Location?

[cunning plan]

I have two 3-pin brake light switches to install (two as I am recreating the dash warning light), however on my RHD '68, I cannot fit the switch directly to the master cylinder as they foul the chassis rail:

From reading previous posts, I knew this might be an issue, so my plan was to run two small brake pipes out at an angle like this to make clearance:

So that would be a male 3/16th pipe fitting, installed into the master cylinder, then a small run of pipe, to a female 3/16th pipe fitting and the brake light switch installed into that.

However, although the 3/16th male pipe fitting does fit in the switch positions of the master cylinder, it does not seem 'right' as they are not the same fittings as the main brake lines:

Plus the brake light switches seem to be an M10 (I can't remember the exact size, but it was 10... something on the calliper measure), where as the male 3/16th is M9 (?):

Hmm :| :?

So, the question is, urm...

1. Is the master cylinder supposed to have a larger fitting installed into the switch positions and I should not use a standard 3/16th male pipe fitting?
- 1a. If so, could I use some kind of adapter, like the fittings that go to the normal brake lines?
- 1b. If not, any ideas how I can complete this install?

:sign0009:

P.S. Why does nothing just fit first time?! :sign0001:

 

[vinvan]

Fitted our master cylinder yesterday (1969 RHD) and both brake light switches fit ok they just miss the chassis rail, do you have the correct master cylinder?, or is it because its a 68 one year only and the chassis rail is different

 

[nora]

My RHD 69 has two short brake pipes that come off the cylinder and go into two three way unions which have the switches on them, these are on the other side of the chassis rail. I did find a photo online that shows this layout but i can't find it again.

 

[cunning plan]

Fitted our master cylinder yesterday (1969 RHD) and both brake light switches fit ok they just miss the chassis rail, do you have the correct master cylinder?, or is it because its a 68 one year only and the chassis rail is different

Thanks for the pictures! arty0021:

It's a '69 master cylinder as you cannot buy the '68 ones anymore. Although I do not think they are that different as they take the same fluid reservoir (100mm apart holes) etc.

Maybe the switches are different. I have chosen the 3 pin, but your 2 pin ones look smaller? :? That would explain why the 3 pin switches do not fit into a 3/16th female brake pipe fitting (if the switch is larger and therefore has a larger thread size).

My RHD 69 has two short brake pipes that come off the cylinder and go into two three way unions which have the switches on them, these are on the other side of the chassis rail. I did find a photo online that shows this layout but i can't find it again.

I know what you mean as I think I have seen the same image, similar to Vinvan's first image on the right you can see a T-piece?

If that is right, then I think using a standard 3/16 male to make two small pipes would be fine. :?

 

[cunning plan]

Okay, so I had a bit of time to fabricate a solution to test using the old master cylinder (new one is on the bus already mounted).

Would this work? :sign0009:

Would the 3/16th / M10 male pipe connector going into the master cylinder leak? :|

Also a bit concerned about the switch going into the female M10 connector as there is no brake pipe to 'crush' inside to make a seal, it is just a flat base of a switch?

 

[cunning plan]

Anyone know for sure? oke:

Logically it seems like it would work.. :?