Spring relocation without mini tub?

What size tires, and is it lowered?
275/35/18 tires on the rear, stock width A-Body 8 3/4 rear end, no lowering blocks with disc brakes, US Car Tool spring relocation kit which has 3 hole locations on the front spring mount, I have the drivers side spring in the top hole and the passenger side spring in the middle hole, I believe the rear shackles are 3 1/2" or 4". Wheels are custom made 18" x 10" with 6.5" back spacing.