I wanted to fit my BMC air filter element into my derv guzzler, and after much head scratching this i what i did.
First stare into engine bay and look at the lack of room.
Then undo the clips that hold the pipe onto the top of the maf and and onto the turbo, i used a small flat headed screwdriver to prize the apart.
Remove the front 3 relays starting from the left, that was ok room for me.
Next get a 7mm socket on the end of foot long extension ( i used a tee bar) and Carefully undo the 3 studs.
If you have managed to get all 3 out without rounding them off well done!
Now a bit of wiggling is needed to get the airbox top up,but it is poosible.
Take out the old filter, clean the airbox out and fit new.
Wiggle the top back into place.
Put some copper slip on the screws and fit and retighten being careful not to drop the socket in or to round off the heads.
Refit the relays.
Put the pipe back on the maf/turbo.
And finally nip the clips back together with your nail pliers (the ones with the curved jaws for getting er nails out).
Bask in the glory of your achievements.