Fat cap down. Ain't no way it "runs through the meat" and it acts as an insulator - not to mention you cut if off and throw it away so why bother to season it!
I like the "meat side" to be pretty much untouched during the cook so my bark stays intact.
However, it's not "wrong" to cook fat up. I just prefer the results I get with the fat side down.
Southern Brethren BBQ Competition Team
"It's all about getting paid!" - Myron Mixon
"I love being hated in my hometown!" - David Hair
KingFisher Gator Rotisserie cooker, WSM, Stainless 5 burner with IR gas grill, Turkey Fryer, Weber JD Commemorative grill, slightly used Bandera chamber for future use as a cold smoker, Masterbuilt 40" insulated ELECTRIC smoker