Mike,
If you have to bed the stock, do so just like you would a rifle. Fill any holes in the action that you dont want bedding compound to get into with clay and then be sure to apply a proper amount of release agent or lubrication to the action so it does not permanently become one with the stock. With that in mind Id take all of the action components out to prevent bedding compound from finding its way into areas it shouldn't.
Is the head of the stock in good shape? If it is oil soaked the bedding compound will likely not stick even if you rough the surfaces up. Why exactly is the tang digging into the stock? Was the stock not properly inlet from the factory? I would look a little further into that so you dont end up with a bedded stock that has the same problems.
