Turbo, yes, I will definitely take the lowering block out. There won't be any need for it with CalTracs 1" lower option on their mono-leaf set-up. With my 2" (total) narrowed rear, the slicks will still fit up in the wheelwells on 15x8 rims with 4.5 backspacing and the slicks. Tread width is slightly narrower than the 275/60-15 tires I have now and diameter is slightly smaller at 27.3 compared to 28". It's a little tight at the front inner wheelwell with the 60s, so it will help in that area too. I refuse to cut anything on the car being an original rust free R-code 4spd car.