Factory service manual contains all information needed on the 1940-1947 Knucklehead, 74" & 80" Flath.. $39.82. Add to Cart... 48-0308 Factory service manual contains all information needed on the 1940-1947 Knucklehead 1940 Harley-Davidson EL Knucklehead | F141 | Las Vegas 2023 Harley Davidson 1936/1947 Knucklehead - The Garage Sale 44 Michigan Motorsports MR2 3 Pin Alternator Adapter Round To 3 Pin Oval Plug Harness Fitment for Toyota Vehicles. 5.0/5. Product ID: 155588994. Free Shipping