I've got the same gun, the load Rebel gave you works like a charm. I run the shot load a little higher 1 5/8, other than that the same.
Only advise I have is try to get out and shoot it some before going into the field. More than likely one barrel will not be hitting POA, would be good to figure that out before the hunt. Shooting will also get you use to the gun. Double barrels are trickly just because you have to break some old habits about loading and firing when operating one. Sounds simple enough but, muscle memory and routine are hard to break sometimes. I found it took a few session at the range shooting mine before I was comfortable with it and not making mistakes in loading and firing.
Something else to try, load one barrel kinda heavy, say 105 grains, leave the other barrel empty but, pull the hammer back on it while firing the other off. The test here is to see if the second hammer will drop from the recoil, it shouldn't! If it does obviously you don't pull both hammers back to battery then fire. If you get both those barrels going off at the same time, you'll be a hurting.