Need Tools: Adjustable Wrench Installation Acrylic Base Steps: Step 1. Tum the tub over and place on a non-abrasive mat, be sure that the tub will not roll aver and will remain stationary. Step 2. Take the bathtub bass, tum it over, and align the four holes with the four bolts on the tub. Slowly lower the base until the bolts have penetrated the holes on the bass. Step 3. Apply a washer to each of the four bolts then apply and tighten the lack nuts onto the bolts by using an adjustable wrench. Step 4.