My question is where to install a P trap on this configuration (Disposal is directly over the drain pipe). We are on conventional foundation, so is installing P trap under the house an option? We went from a double sink to a single deeper sink and there was only 6 inches of clearance so I took a chance with no P trap....bad idea. Sewer gas now coming in regularly. Any help with details and illustrations from a plumber would be much appreciated. Thanks!