First thing is you need more roll out, ie a taller tire 29.5 would probably solve 90% of your issues. Way to much power for a 27in tire to handle without a wicked suspension. Second I would ditch the 90/10's and get some Vikings up front. You will then have way better street manners and WAY more control of what the car does. Then a true antiroll bar as illustrated above. That would be my approach
Ya I've told to ditch the 90/10's before I will be going to a taller tire in the future but probably 28", I'm running 3.73's
I also run 3.73's in mine with 28"x12.50 ET Streets. The car has run a best of 10.96 at 124.72 with only high 1.5's to low 1.6 60 foot times, always thought it should do better. I had already planned on ordering either the BMR bar or the Spohn bar in a few weeks anyway. After reading this thread, I just ordered a set of the Moog springs Hugger suggested from Advance Auto Parts, 20% discount and free shipping came to $60.63. They will replace the worn out original Skylark 350 springs that are in it now. Can't wait to try them out. I'm currently using a set of Competition Engineering drag shocks on the front and I will keep them for now. Ken