I just did mine and had to take the seat and tank off. The bolt heads were installed "head down" and the tank was in the way. I had to bend my bars back into shape after a crash. Over the summer I will replace the post with one from Wildchild and go with the forward mount.
In through the top or up through the belly pan, I cant quite remember.
Ive done this a few times and its a very tight fit. I cant remember if the post goes in the top -> down or from the bottom (belly pan) up. Maybe someone else can help here....
It works best from the top. It is best to pull the tank, air box, and unbolt the carbs or TBs and just move them to the side. EFIs are easier because of the oil pump but you just need to unhook every thing and work it through the motor mount and oil pump area. In and out the same way.