I'm 6'5" and had them put a tall boy seat to move me back 1.5". The darn backrest moves me forward 2". Any ideas on this? Are all the Harley ones the same in that respect?
HD has two versions of backrests, one as depicted above, and another which is adjusted pneumatically.
The location of the slot in the seat has much to do with the location of the backrest shown above. If you opted for the pneumatic, you could possibly risk tearing the seat if adjusted as far back as it will go, and then constantly adjusting it.
I've read a few reviews stating it wears out/tears the seat. I've used the pneumatic one for 4 years, (on stock seat) and see no sign of wear or tear. Then again, I found a comfortable position for it, leave it there, and rarely adjust it. Pushing it back all the way, it feels like I'm in a supine position, and no way could I use it if pushed all the way back.
If yours is like the link above, the mount can be manually moved towards the front or the back of the bike. I suspect they didn't move your backrest back, and because the seat sets you back 1.5", by not moving the backrest back too, obviously it feels like it's shoving you forward 2".
Take your seat off and take a look to see if your bracket won't move back a couple notches. Hopefully it's not already located as far back as it will go.
Edit: Looks like Smokey and I were typing the same time, but yeah, what he said too.