Note that these kits (made by V Twin Mfg) set the springs at 7 1/4" centre to centre, and that the seats commonly sold on ebay by the same sellers DO NOT FIT the kits. Sellers are legendsmc, justified_defiance, motherroadcustoms, gnlemont.
This is because the commonly sold seats(such as the bates replica) have mounting studs 6 1/4" inches apart.
The kit supplies a bracket that is meant to adapt for these seats, which does not work:
1. the holes are in the wrong place on the adaptor bracket
2. the bracket when fitted looks ugly and bad
3. the bracket causes the seat nuts to rub/sit on the springs, and the bracket nuts rub on the seat vinyl
Other than that the kit is good.
But because of the above, I had to take the whole seat apart, cut off the studs and get new ones welded on at 7 1/4", then put the seat back together.
The sellers tell you that the seats fit the kit. THEY DON"T.
If you want a seat that fits you have two choices:
1. Do what I did by modding the seat
2. Buy a seat with mounting studs 7" to 7 1/2" apart, then it will fit. Make sure the seat will look right with the bike.
Note that some sellers told me their seats were 7 " or more c/c, but in fact they weren't.