The sensor is very easy, but tight to replace.
The rear camshaft seal is not easy to replace. The MTX is probably more difficult to replace than the ATX since the ATX is further forward and would likely be more easily accessible.
I replaced the cam seals (all three) on mine as part of the front end 60K back in May.
In order to get to the rear cam seal, I unbolted both motor motor mounts from the subframe and used a floor jack, properly supported under a 2 X 4, to lift the whole front of the engine up as far as it could go. I already had the Y-pipe dropped, the fuel lines disconnected, and the passenger side halfshaft removed, so I got a lot of elevation of the engine to get to that seal. Once the sensor was removed from the housing, the housing was removed (2 bolts). The old seal was removed by drilling a small hole in it, screwing in a small sheet metal screw and prying it out. A new one was pressed in using basic hand tools. Sergio down in Houston had told me how to do this and I am happy to pass on his tips.
The two middle camshaft seals require that the timing belt gears and the inner timing cover be removed. Other than that, they are easy.
Steve
