I have just done this on my W Reg 55 Van. It was trickier than it looked as Gavin says, it'd be great if you could just jack the engine up but sadly it drags the car up with it so I worked this way out. You will need:
13mm socket & spanner
15mm socket & spanner
axle stands (unless you're Dangermouse!)
a friend might help for one bit!
Firstly check handbrake and undo the 10mm nut on the air filter box then lift it up and away to get better room to work.
Then put the jack under the gearbox, I found the joint between the gearbox and clutch bell housing was ideal, raise it just to take the weight off the old mount. Undo the large central 15mm nut then undo the 13mm bolts which hold in the retaining plate, the rear one is a bit of a sod the get to, ring spanner works better than socket here.
Having removed the retaining plate undo the 15mm nuts holding the steel mount which the threaded portion of the mount goes through. [media][URL=http://s1065.photobucket.com/user/bonzo1974/media/Escortgboxmountsteel.jpg.html][IMG]http://i1065.photobucket.com/albums/u384/bonzo1974/Escortgboxmountsteel.jpg[/IMG][/URL][/media] I found I could only get the rear one off with a spanner at an angle.[media][URL=http://s1065.photobucket.com/user/bonzo1974/media/Escortgboxmountrearsteelnut.jpg.html][IMG]http://i1065.photobucket.com/albums/u384/bonzo1974/Escortgboxmountrearsteelnut.jpg[/IMG][/URL][/media]
Then undo the bolt holding the aluminium cast mount to the car on top[media][URL=http://s1065.photobucket.com/user/bonzo1974/media/Escortgboxmountaluminium.jpg.html][IMG]http://i1065.photobucket.com/albums/u384/bonzo1974/Escortgboxmountaluminium.jpg[/IMG][/URL][/media], then following the casting down you'll find a 15mm bolt under the car which you remove. [media][URL=http://s1065.photobucket.com/user/bonzo1974/media/Escortgboxmountaluminium2.jpg.html][IMG]http://i1065.photobucket.com/albums/u384/bonzo1974/Escortgboxmountaluminium2.jpg[/IMG][/URL][/media][media][URL=http://s1065.photobucket.com/user/bonzo1974/media/Escortgboxmountunder.jpg.html][IMG]http://i1065.photobucket.com/albums/u384/bonzo1974/Escortgboxmountunder.jpg[/IMG][/URL][/media] Make sure you have put axle stands under before going beneath - I don't want to be sued any time soon!!
Once all of this is loose it is just a case of doing the dance of the lifty lowery jack until you can get the mount out - it's still fairly awkward but it will come out, then replacement is just the reverse using threadlock wherever needs be, the friend is to wiggle the ally casting while you're under trying to locate the bolt! A pry bar can be useful.[media][URL=http://s1065.photobucket.com/user/bonzo1974/media/Escortgboxmountfinalstage.jpg.html][IMG]http://i1065.photobucket.com/albums/u384/bonzo1974/Escortgboxmountfinalstage.jpg[/IMG][/URL][/media]
Enjoy your van/car which no longer rumbles/judders in reverse and kerklunks when you turn her engine off, bear in mind though that because there's more contact in the new mount there will be more engine vibration through the cab.
Hope this helps someone else, and hope the photos work!!