Seeing as how I've spent the last couple of days staring at these from a distance of around 30cm...
The rear gearbox mount will be a PITA to replace, should you need to.
Fortunately, it's a fairly substantial thing. My Jazz has done 130k miles and the mount looks like new.
If you DO need to replace it, I'd suggest loosening all the other engine mounts, split the join between the exhaust manifold and the cat', removing the bolt from the middle of the mount and then wriggling the engine forward to give yourself space to get to the other bolts.
The mount on the right side of the gearbox is similar to the rear one, with the benefit that there's easier access to all the bolts.
The weakest mount is the one on the "front" of the gearbox (actually also located on the right side of the gearbox but facing forward).
That's got a "rubber spider" in it which is pretty flimsy and is likely to need replacing if it hasn't been done before.
The bolts for that mount are kind of fiddly but it's possibly to get them off from underneath the car with a regular spanner (no room for a socket), with the wheel off.
The engine mount, itself, is also pretty tough (again, still like new on mine).
The only awkward thing about removing it (or loosening the engine/gearbox mounts in general) is that you're going to need a deep 14mm socket to fit over the long studs in the engine mounts.
Support the engine with a trolley-jack, remove the solid part of the mount from the engine and you can undo the bolts and remove the rubber mount.