Just so everyone knows I wound up cutting 1.5 coils off the 2" lowering springs and after a week they are sitting about where I want it. It'll probably settle more. I have just enough room for 28.5 inch tires.I agree with Northernregal . This is not the way this works, unfortunately. You're making the same assumption that I did the 1st time I tried adjusting ride height with different springs from different engine setups. I tried two different sets of springs and ended up putting the original saggy springs back in. And they were in that car until it's untimely demise. That car had varying front end weights as the power plant changes occurred. And FWIW, as the heavier the front end got, the better the stance - and the handling didn't get worse. Of course this is my opinion, but I can safely say that car was glued to the road as compared to my MC.
In my current car I have V6 springs from a V6 car with AC and they look original for whatever that's worth. I've deleted all of the heating and a/c system including inside the car. I've added a 4L80 (+100lbs), 4.5 gallons of ATF (20+ lbs), T6 turbo (+50lbs), piping/intercooler/piping/30x12 trans cooler/etc. (+40-50lbs) - and it rides great in straight line, but not much for handling with skinnies on the front. Point being, the V6 springs are adequate and my ride height is not too low. You can find pics of the stance here if you look.
I agree 200% with what Jared is indicating. I was told this by my local spring shop guy, that was a genuine hotrodder in his younger days. He explained this to me when I was swapping springs and the problems caused by cutting springs and how the results are somewhat of a crap shoot. Others might disagree, but ......
arlowf This thread is describing every reason why guys swap to coil overs. Every coil over manufacturer has various springs for rate and height specs. Regarding your shop doing the work and multiple calls to UMI, I'd be concerned that you might at the point where you're wearing them out. I know when this happens to me (similar business), I get to the point of telling the customer 'yes' to every question just to get them out the door. I know that isn't the right thing to do, but when someone isn't picking up what I'm putting down, then it's time for me to move on.
Either cut the springs as UMI has suggested or save for an a-arm/coil over package - my best advice.