MacDon FD75 OM - Manual (Page 220)

HEADER ATTACHMENT/DETACHMENT
5. Remove locking pin (A) from adapter pin (B).
Figure 5.39: Locking Pins
6. Lower handle (A) to engage adapter pins (B) into
feeder house. Reinsert locking pin (C), and secure
with hairpin.
Figure 5.40: Engaging Pins
7. Unscrew knob (A) on combine coupler (B) to release
coupler from combine receptacle and clean coupler.
Figure 5.41: Combine Coupler
169894 206 Revision A