brake switch or 4 way valve question

[1 tuff z]

i've recently upgraded to ross' [modern motorsports] big brake kit [rotors-13's front 11's rear] and my car at threshold still wants to lock the right front first. it has done this since i've owned it and i always assumed that it was an imbalance in the calipers or...something i couldn't determine. the following are new-flex brake lines [braided stainless], all calipers, rotors, wheel bearings, master cylinder.

 

now as i try to pin this gremlin down i'm considering that potentially one of those 'junction blocks' [for lack of a better term] under the hood may be the culprit. in the vic brit catalog they are labeled; brake switch assy [the one on the left side fenderwell fwd and below the master cyl] and the 4 way valve assy [the one on the firewall below the fixed portion of the hood latch assy.

 

i wanted to know if anyone else has run into this problem before and if there's a way to test/service either of these components.

 

any help, greatly appreciated!

[260DET]

What you could do is disconnect the front brake line from the master cylinder and one of the caliper lines. Then blow air through the line to check that it is clear. Repeat the process with the other caliper.

 

It is not a bad idea to do this anyway with all brake lines when doing a brake job. Not sure how the proportioning valve would affect this for the rears though.

[1 tuff z]

latest. i removed and cleaned the 4 way switch assy. [on firewall]. it had some dirt and what looked like an ivory colored grease inside. re-installed, test drove and...same problem.

 

any ideas, cause i'm fresh out?!