TM 9-2320-209-20-3-4 b. Replacement. (1) First reduction drive chain. FRAME 1 1. Put chain (1) in place and put detachable link (2) through ends of chain. 2. Put on keeper (3) and clip (4). 3. Adjust first reduction drive chain (1). Refer to para 19-18. GO TO FRAME 2 19-91