Well, Chris of Lentech emailed me back. The trans has to come out. Here's his answer: "The solenoid pack on the valve body cannot cause a flare as they are ON-OFF solenoids. They will work or not work (ie: you will have all gears or not). The potential causes of a 3-4 flare as I see it are larger than spec clearance in FWD clutch or worn OD band. Just to be sure you don't have a pressure problem, you could put a gauge on main line and verify it is in range." I'm certain my pressure is ok, but even if it wasn't, either the trans or the motor comes out (If the pump needs doing, the whole trans gets massaged). Don, it looks like a higher performance Forward clutch drum will be going in.