Ok, as prompted by
@StarCruiser, some photos are needed, I’m thinking ...
Don’t know the Thule product number for this one, but it’s super strong and the clamping device to a tow-ball is ultra positive...
I could stand on this and do a jig without it moving...
And with a couple of bikes...
My only concern is how low it is, the bottom of the wheels is at tow-ball level.
As it’s a receiver mount, I’m going to get a riser tube made up so that the rack is above “rear-ender shunter” level...
Maybe as high as the top of the spare, with the rack angled top forward so that the bikes lean towards the front of the truck on the same slope as the rear windows.
However, I don’t think this arrangement would work very well with a tailgate...
