The unbalancable trem

Hey guys!
I'm working on my 6th Pitbull build but am having issues with my first, an ST-1.
I never bothered to use the trem, but now I want to set it up to work!
I am no newbie to setups and balancing strat style trems, but this particular one seems impossible,
It is always too stiff to use while playing, but whenever I release tension from the back (be it from either the claw or springs), the bridge floats WAAYY too much (and even then the bar is still stiff).
The only thing I can think is that it is related to the angle at which the strings come off the saddle (on the ball end side), but I can't think of a way to widen the angle without lowering the saddles (and planing the back of the neck to adjust the action).

This is the stock bridge with the kit. I may have to just buy a different bridge.

Has anyone else had this issue? Or know another way to fix it?

The way I used to set the bridge on my Fender Mexican Standard Strat was to use two pieces of hard material about 1/16 inch thick (sorry about the imperial measurements) to lift the back of the bridge up from the body of the guitar, then I tightened up the springs almost all the way, next I went through the process of setting the individual string height for each string after tuning the guitar up to pitch and then finally set the intonation, once that was done I gradually loosened off the spring tension till the two pieces of hard material fell out from under the bridge, once that was done the trem system was set up to float, you can reduce the stiffness of the trem system by removing a spring, usually three springs is enough for 42-09 gauge strings.

Hi Xmalice, welcome to the forum, you built 6 kits and this is the first we heard from you ! What other kits have you built other than the ST-1 ?
I've built about 15 or more ST kits and never had this issue.
How is the action are the saddles set about midway height ? Is the neck fairly straight under string tension ?
Maybe the 6 bridge screws are too tight and making the tremelo hard to pivot ?
I'd mess around with the spring tension and even try hooking the 2 outside springs on different mounting holes to experiment. I usually put my outside springs angled to give more tension. Let us know how you go

To set the 6 bridge mounting screws so that the bridge pivots on them correctly, here's what you do, firstly hold the bridge so it sits flush with the body of the guitar next tighten each screw so that the head of it just touches the bridge, next loosen off each screw about 1/4 of a turn.

The bridge should pivot easily on the 6 bridge mounting screws.