the thing to do mate is to undo the torque convertor from the engine, i.e leave it attached to the box. when you do this just hold it in place with a couple of cable ties. then you don't have to worry about the seal on the gearbox pump. then you can take the engine out, change the seal, then but it back in and re-attach the torque convertor, i is only 4 bolts on a standard box which isn't to bad compared to my racer which is 8 bolts. just make sure when you do them back up you put some lock tite on the as you don't want them to come undone as it will bend the flexi plate if they come loose. any problems then give me a ring you have my number.