I'll give ya mine, use it if ya wan't:
Slaughterhouse Poultry Brine By Tip Piper of Hillbilly Vittles
1 ½ Gal Water
½ C Salt - Kosher
½ C Dark Brown Sugar
2 tsp Garlic Powder
2 tsp Onion Powder
2 tsp Cajun Spice (Louisiana Cajun Seasoning)
2 tsp Celery Seed
Slaughterhouse Poultry Injection
½ Pkg Good Seasons Italian Dressing
2 tsp Garlic Powder
2 tsp Celery Seed
2 TBS melted Butter (non salted)
2 C Apple Cider
Slaughterhouse Spritz (Good fer everthin!)
8 oz Apple Cider
6 oz Water
4 oz Whiskey
2 oz Cider Vinegar
As far as rubs go, do a google search, there are so many out there, you need to pick one that sounds like what yall wan't.
I don't spatchcock my birds, I use the beercan holder an just stand em up. Or ya can lay em down, I do breast side up an take em to 170° in the meaty part a the thigh er the breast.
9 lbs? Wow, that one gonna take awhile, thins closer to a turkey then a chicken! I'd run the smoker at 300° er better to get through the 40-140 zone in that 4 hour period quicer. I'm guessin yer lookin at 4-4 1/2 hours maybe on that one.
Why don't ya wanna brine? It really makes a difference in my opinion (an my customers too!). But to each his own, the injection I gave ya I use on turkey's but that beast a yers would prolly do well with it to.
Good luck.