ANSWER: This will not be a good fit. The truck will not be able to handle this much weight with 2 bikes on the back. I would suggest hauling only 1 at a time.
1974 honda CB360– 392 lbs
1971 Honda CB175 – 299 lbs
The double motorcycle carrier only has a carrying capacity of 600 lbs total between the 2 rails. Sorry, this will not work.