Do it in a pan, you'll still get smoke.....if you don't, it will be a gigantic mess his gasser may never recover from........................
Burner on, on one side, panned pork on other or in middle with low burners either side......
Fun part about a pan is you can add in some liquids & get a partial braizing that way....gas tends to dry things out sometimes & that fixes that..............
Run up to 175~180 int, then cover the pan for 1-1/2hr., maybe....that will speed the finish some.....don't know about crispy bark doing this....just not the same deal......
I walked a guy thru a pork butt on one of those box grills, like gas, charcoal, infrared 3X deals, on the grill.....
charcoal straight under a butt, "Z" shaped snake of charc. with wood blocks.....it worked.....if that guy could do that, anything's possible...........