I will do a how to when i change my LIM..hopefully in the next couple of weeks.
But in the meantime..UIM removal is just a case of removing all the vac pipes (wrap masking tape round em and mark them up so you know what goes where..or take a few pics), disconnect the larger black vac pipes by pushing down on their outer sleeve and pulling up on the pipe, un bolt the egr valve if you have one, remove throttle cable, TB bellows and cables, unbolt the UIM itself and remove..it takes a bit of jiggling to get it out and away.
You are now free to remove TB and scrub away.
Most of the muck will be around the TB mounting and you can remove this easily..just be careful that whatever you try and clean the UIM internals with isnt abrasive..you dont want any bits getting inside and sticking in all the oily deposits in there only to come away and end up in your engine.
I happened to have a botle of BBQ cleaner which was a mild caustic solution..filled my UIM up with this and left it overnight, then gave a good thourough rinse with a hosepipe and left it to dry for a couple of days...the **** that came out was shocking.
Hope this helps for now.