Lay out all the pieces and check the instructions to make sure everything has been included with your weight bench. Attach the cross brace to the left upright beam and repeat the process for the right upright beam. Tighten them together with carriage bolts and set the backrest adjustment bar onto a slot on the upright beams.
Connect the main seat support beam to the cross brace with two carriage bolts, two washers and two nuts. Do not completely tighten the nuts in place. Attach the main support beam to the front post with Allen bolts and washers. Connect the diagonal support beam to the front post in the same manner. Attach the the other end of the diagonal support to the main seat support beam.
Place the arm curl stand in the front post and secure it in place with a lock knob. Tighten it down completely. Connect the leg developer post to the bracket on the front side of the front post. Attach the arm curl handle to the open bracket on the leg developer with an L-shaped lock pin.
Attach the bracket supports to both ends of the pivot arm of the support beam and lay the other ends on the backrest adjustment bar. Connect the backrest board to the supports with four hex bolts. Attach the seat pad with four hex bolts onto the main seat support.
Secure the preacher pad arm to the curl stand with two Allen bolts. Put two foam tubes into the leg developer halfway through the holes and attach the four foam rolls onto the ends of the tubes.