I used a HF metal chop saw to cut mine to the right length. This shortens the total length... I think Kubota did this intentionally because the longer the insert the more weight/torque there is on the rear frame which is, after all, not a 1 ton pickup frame.
Did this twice...two different ball sizes, easy to swap out. Both inserts were the hollow tube type.
I thought about drilling a second hole, but decided that the two holes so close together would not be a good idea, weakening the insert should I ever wish to use it in a pickup again.
On the 1140 with both my modified inserts, the ball is right at the edge of the tail gate or barely beyond. I can't imagine an attachment that would hit the bed during a turn, but as always, be careful out there:thumbsup: