I'm trying to replace all the pvc plumbing under my double kitchen sink (it was actually duct taped together before). I'm adding a direct connect tailpiece for my dishwasher run off (I'll won't begin to mention how the previous owners had it rigged) but no matter how short I cut the tailpiece and the Tee the drain arm still comes up about an inch lower than the top of the p trap (which drains strait back to the wall if it matters). I'm guessing that the sink is too deep and that the dishwasher was added after it was installed? Is there any way to add an extension to lower the p trap? I looked at Lowes but didn't see anything that would work.