It's pretty straightforward as long as you are careful and logical.
You will need to be able to support both the engine and the gearbox independently. I use a engine support beam across the top of the engine compartment to support the engine and either a trolley jack or another lifting point on the same support beam to support the gearbox. It's heavy!!
You might be OK using two trolley jacks, but I would recommend buying an engine support beam!
You don't need to remove the subframe (well, not on my 1.8l 5-speed box anyway).
You will need to remove the lower links between the subframe and the front of the engine bay under the radiator. (it's the silvery "bar" that runs left-right as you look at the engine bay through the wheel arch)
You need to remove the nearside driveshaft. You can leave the hub and suspension in place (leave only 1 bolt in the strut-hub joint so it's bendy).
Cut the cable tie and pull back the gear selector rubber boot. Remove the bolt in the middle. Don't touch the "clamp" bolt on the shaft! If you have the cables, then they're easy to remove.
Lift the engine slightly, remove the gearbox mounting completely. Remove the lower link at the back under the engine.
Just go round the outside of the gearbox-engine mounting and remove all the bolts and nuts except the top two.
Lower the engine as far as you can before you strain the exhaust and/or the o/s top engine mount.
Support the gearbox, carefully remove the top two bolts and carefully move the gearbox and engine apart.
You should find that the o/s driveshaft will just disengage and remain "in place" because of the fixed bearing on the back of the cylinder block. If it's sticking, then you'll probably need to release the bearing from the engine and remove 1, loosen the other o/s strut-hub bolts so you can move the shaft away from the gearbox (once you have freed it from the box).
It's a bit of a slag. You'll need to move the engine about a bit to get clearance for the box to separate and again more manoeuvring to get the box out of the engine bay. Be careful not to damage it or the other items in the engine bay. The hydraulic pipe for the power steering is a pain and keeps getting in the way.
Refitting is usually a pain. Expect to spend between 5 and 30 min trying to get the gearbox to locate properly into the clutch. It's hard work. Sometimes you can be lucky and it just slides straight on, other times it can take ages.
So in summary: It's not hard, just time consuming and a bit tedious. Just go slowly and be methodical. Photos of pipes/cables etc are a great way to remember how it goes back together. There are some cables that need to be on the correct "side" of the gearbox.
Have fun!
John
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