The horizontal mounting holes are 5" inches apart (center of hole to center of hole)
Very early models of these tractors had 1-1/8" inch PTO output shafts
The last photo shows how the bracket mounts to the floorboard
L306D12 Undermount and Mid-mount Allis-Chalmers D10
New Pair of Back Cultivator Spring Arms for International and IH Farmall 140
New Governor Arm for Farmall A, AV, B, BN, C, Super A, Super C, 100, 130, 200, 230 Tractors The horizontal mounting holes areNew Governor Arm for International and IH Farmall A, AV, B, BN, C, Super A, Super C, 100, 130, 200, and 230 Tractors and IH 57 Balers. Replaces Case IH Governor Arm part number 6507DA. All governor related parts