brake light and turn relay

Hi, new here.

I have a wiring kit that I bought from E-Z wiring for my 67 buick, problem: I have no turn signal hardware in my buick there fore I have no brake wiring too, I wonder if anyone of you members have any drawings on using a 12dc relay that will activate my brakes but will not interfere with the turn signals, here is a picture of the wiring that I have

what I think will work is adding a relay so when I press my brake it will turn on both the blinkers such as the next picture

do you guys think this will work? but will not cause both blinkers to turn on when ever I hit my switch to turn on the left or right blinker. What relay do you guys suggest?

You can do it that way, as long as you use a DPST or DPDT relay.  If you use a standard SPDT automotive relay you will not have isolation between the left and righ lights.

If you only have access to SPDT relays you can use two of them, with both coils wires to the brake switch, and each individual set of contacts wired to an individual side.