well went to change the air filter today but the under tray bolts just kept turning round and round without coming out so i disconected the 30mm pipe below the air filter box, dont no what this pipe does but it had a very very small amount of oil drips from it after id disconnected it from the small plastic tank it is connected to, may be its an oil catchment tank, any way unclipped the clips either side of the filter box pulled the old filter out and pushed the new filter in and done the clips up,and refitted the 30mm pipe, so theres no need to take the under tray of the jtd if you cant remove it,