I sent this to Rivco in the hope that they would build these brackets for others that wanted to use their risers. I don't think that has happened so here is what I sent them on how to remake the tank bracket.
Trapper
To Rivco
To begin I decided to build a whole new Bracket because I thought if I destroyed the original one and it didn’t work I would have to buy a new one. So I started with a 1/8” stainless plate and cut it out so that it would be in two pieces. Then made a hinge out of a three small pieces of ¼” ss pipe, welded them on the flat pieces and used a 3/16”ss bolt with a self locking nut as the hinge pin to put them together in the middle of so that it will let it bend down past the handle bar bracket. After making it I think you could cut the original bracket into two pieces and weld or bolt on a small hinge or maybe just find a gate hasp that already has the hinge and cut it out to fit all the other requirements. However both of those options would require some type of painting maybe a power coat. Once it is on you still need to remove the two bolts that hold on the tachometer and speedometer and move them off to the side and then the hinge will allow the bracket to bend down and pass by the handle bar bracket. It works great and it takes about the same amount of effort and time as the original Rocket 111. One other thing is that if you purchased ABS as I did you will need to disconnect the front break line and run it behind the bars.
In the pictures I sent you I have a couple where you can see the original bracket side by side with the new one. I also included the fab drawing of the one I made the only part that isn’t shown is the slight bend which you will see that is required on the slotted part which bolts the tank to the bike.
If you need anything else let me know
I hope this will help you