[PukkaSilvia]

At turbo gasket is not too hard of a job second time around. The first time you do it you may struggle a little

You can do it by the side of the road. you do it from above the car rather than from grovelling in the dirt.

Disconnect the turbo oil return line to the sump

Get yourself a 13mm spanner and cut it in half as a couple of the nuts in a tight space.
Support the exhaust at the front on a trolley jack
There are locking tabs bent over the 13mm nuts that hold the turbo to the manifold so bend them up first and then undo them.(theres 4)

Lower the jack and see if the turbo comes down enough for you to slip a new gasket in. If not either it needs the rust/heat cycle seal broken by tapping it with a hammer or prising it apart with a screwdriver.

Check that there are not any hangers on your front exhaust section that may stop you from lowering the whole lot down.

A turbo gasket is about £15


As for rear calipers. check its not a seized cable or just that its discs are not rusted up and just needs a drive. The pistons can seize.check them by using a grinder disk key with the pads out. they go in by rotating them with the key in there tabs.