E30 seats are notorious for breaking the brackets that mount the seat back to the seat bottom. The stamped metal used there has two failure points – one at the welded nut and one at the 90 degree bend. Fixing is possible by way of welding, but the bracket often re-fails slightly up or down stream of the welds. The bracket below had already been welded once and has broken again at both failure points: Removing the broken bracket: The bracket is attached to the hinge with a single steel rivet. Grind or drill off the rivet head, push the rivet out, and the bracket comes right off: The permanent fix: Once removed, you can use our repair kit to permanently solve this issue. The new bracket is CNC machined from solid billet — the thread is machined directly into the material, so there is no welded nut to crack off and no thin bend to fatigue. It is completely weldless and bolts on through the two existing holes with the included hardware: Available here: https://www.rtsauto.com/e30-seat-back-mounting-repair-brackets-tabs-sport-comfort-4-door-2-door/ Seat hinge interchangeability (2 door, 4 door, convertible, Sport, Comfort): All E30 seats except the early 84-85 seats have interchangeable seat hinges — 2 … Continue reading E30 Seat Hinge Interchangeability (2/4 Door/Comfort/Sport) and Failure Point (Broken Seat Back Mounting Bracket)