Make the glaze by combining brown sugar, garlic, green chile powder, ginger, thyme, smoked paprika, black pepper and ground chili pepper in a bowl.
Add orange marmalade and orange juice to a small pan with brown sugar and spice mixture.
Whisk together and cook over medium heat, bringing mixture to a boil. Lower to simmer, cook 10 minutes, whisking occasionally. Set aside to cool.
Slice sirloin steak into 1/4 inch by 1 inch slices.
Peel and devein shrimp.
Thread steak and shrimp into skewers.
Place kabobs in a 9 x 13 inch baking dish.
Pour half of orange glaze over the kabobs. Reserve the other half of the glaze for serving.
Cover and refrigerate skewers while the grill fire is prepared.
Hickory or pecan is great to add for smoke flavor. Build a grill fire to about 350°.
Cook kabobs over indirect heat with the grill closed about 10 minutes.
Check internal temperature of steak and shrimp using a digital thermometer.
Steak should be at least 135° and shrimp should be 145°.
Remove to a platter and serve immediately with remaining orange glaze.