Rear disc conversion and big brake installed BUT..., ...having small issues Options

[conus00]

As title says I have had recently installed rear GT disc conversion along with 13" Wilwood brake kit. I would have done it myself but because of the weather/time restriction I had them installed by mechanic in the shop.
First of all I have to say that I am impressed: the stopping power is amazing and it was worthy every penny I spent on this upgrade.
Now the issues:

(1) I'm not sure if the GT parking cables are longer but right now, when I engage the parking brake, I have to pull the lever about twice as high than before. It does not bother me (as long as my parking brake works) but it was much more convenient before when I had to pull the lever up only about three inches to get a grip. Is there any way how to adjust the parking brake lever height?

(2) The second (and more pressing) issue is that now after the swap my brake pedal engages at lower half of the pedal height. When I used to have drums in the rear it engaged right on the top (all I had to do was "tap" the pedal and I immediately felt the brakes grabbing). Firstly I thought that the circuit needed to be bled more (that there was still some air in the system) so I took the car back to the shop. After the mechanic drove the car he gave me the following explanation:
The front discs/rear drums works the following way - the drums engage first and then the pressure goes to the front. Also on the drums there is the way how to adjust the height where the pedal "grabs". As opposed to front discs/rear discs where the brakes engage diagonally - front left with rear right and front right with rear left. So according to his explanation the proportioning valve for front discs/rear drums distributes the pressure differently than front discs/rear discs one.
He suggested that replacing the OEM proportioning valve with aftermarket will fix the issue. Before the swap and upgrade I was afraid that I might need to install one because of the bias, now I'm curious if installing one will fix my issue with "low pedal"?
I'd appreciate any insights on this. Also, has anybody here ever installed aftermarket proportioning valve (like Wilwood 260-11179) on their Celica before?

Thanks!

This post has been edited by conus00: Mar 31, 2011 - 10:29 AM

[conus00]

That's good reading. Is Celica same/similar to Supra?
Do you think that I should try to bleed the system some more before I start making any changes to the pedal height?

Also, I noticed today (it was raining and lot of water on the roads) that when I had to hammer my brakes hard, the car tends to fishtail a little bit. Not too bad but definitely noticeable to my previous setup.
Do you think that installing either GT or aftermarket Wilwood proportioning valve will solve this?