Why not just weld on or bolt on a prefabed piece that the lower links and sway chains can be fastened to. Probably a lot easier and leaves the plate intact.
Remember all the dimensions do not have to be exact. Just clear the tires and be able to spread for attachments. both the lift rods and sway chains could use chain as you do not have any downpressure on the B7100 three point.
Probably critical would be the distance from the tractor to impliment attachment point and the distace for the lift arms.
That is alost the exact setup as on my tractor. The lowerlinks could be straight as the ball/ socket for the pin can rotate to accomadate different width attachments.