You can use the mounting brackets off your 1.4 engine. You'll need to replace the SPi fuel pump with an MPi one. It's a good idea to replace the plastic fuel lines with metal ones aswell to cope with the higher fuel pressure coming from the MPi pump, although you don't have to - your choice
For the exhaust, you could use the manifold/downpipes and exhaust system as used on the 1.4/1.6 MPi Astra 3s.
As for wiring, not 100% sure, but it shouldn't be too hard if other conversions are anything to go by. It's usually just a case of getting a permanent live feed to the engine/ECU loom, connect up the fuel pump wires, switched live and colour match the rest (rev counter, oil pressure etc) - I'm sure someone on here can give you a detailed description
Have you got the Nova GTE gearbox? You could use your existing one, but might find the F13CR a bit of an improvement where acceleration's concerned
You can use your existing driveshafts.
For the wiring, the easiest way to do it is probably to unplug the ECU under the dash and pull the loom through the bulkhead into the engine bay. Leave the wiring attatched to the engine while you remove it. You should see which wires you'll need to cut/join to your own loom then.
You might be better off getting the engine out of a Mk3 Astra 1.6MPi (same engine as Nova GTE). You never know, the wiring might be a bit easier for you, one Astra to another and all