As Ted mentioned, the connector is quite soft. Give it a smack and shape it the way you want. To mount one on a stock that is going to accept a Fulton receiver, you simply need to remove a small amount of wood in the stock so the base can move out slightly to accommodate Fulton's wide rail.
This is a photo of a few of my earlier M14 type rifles. I use Hawk's kits on all of them.
Semper Fi
Art