they have lowering bones that go as low as 2 1/2 then you can turn down you coil over too' I have lower my bike 4 in and it all good.. but I don't have many passenger on my bike . just look on ebay there like 100.00 ship.
You definitely don't want to lower a Jackpot 2-1/2"! Unless you want to blow out your rear lighting harness.
From the factory the JP gets a 1" shorter shock than a Hammer, hence the same frame, but 1" lower seat height.
If you want to lower a Jackpot, you definitely want to go no more than 1.25". Any more, and you'll bottom out constantly, even with your shock preload cranked way up, which BTW makes it almost a hardtail. Being a Jackpot owner, and luckily a Vic parts fabricator, I put our 1.25" drop polished SS lowering links on it. The look is awesome, and handling is just fine. Just have to be sure to move your harness over up under the fender as well as tighten up on your shock preload some to stiffen it some so it doesn't want to use the extra 1.15"s of travel that it used to have.
You're the first I've heard having done that. I I assume you were painting it anyway, otherwise welding a plate in would make a mess of a good paint job. Simply moving it over and securing it with wire ties to the fender supports does the trick for most without getting too complicated.
Oh i did repaint the bike i weld the plate on the reinforcement, not the fender .. wow that would be a lot of work , it did not take long tho.. you way works well also ..I had my bike torn down so i did it.