Aha! Sorry, I misunderstood. Unlike Joakim, you are going for a transverse mounting, which makes a lot of sense. Cable gearchange has come a long way since the Morse teleflex days, so you should be able to adapt the production car linkage without much difficulty.
In fact, I see the Alfa Diva concept eschewed the in-line V8 of its inspiration (Alfa T33) in favour of exactly this arrangement (transverse V6). So all you would need to do is lock-off the steering (watch the geometry, or you will get odd rear-steer effects) and use the struts for the rear suspension, which has the advantage of being rated for the weight of the engine and transmission.
Access to engine service points will be poor though, I know this from experience
Instead of covering the engine at all, just put slats across where the rear window would be in the hatch, like the 6C did. I have a similar louvre over the engine bay on the Nova and because the engine electrics are tucked up under the bodywork (my Nova is mid-engined rather than the more common rear-engine configuration), it never gets wet, even in torrential rain. That way everyone can see your intake plenum (polished, naturally
) through the side windows, and you get the advantage of hot air extraction from the engine bay, which helps cooling.
The guys are right, put the fuel tank in front of the forward bulkhead, as far back as you can so that fuel use won't affect the balance. If you profile the front of the tank to make a wedge you can use it as part of the radiator airflow management (don't forget to put extractor vents in the top of the bonnet to let the air out - they need to be placed far enough forward to avoid the positive pressure area over the scuttle).
As has been said above, make the centre bulkhead the structural "heart" of the chassis, with a strong perimeter frame around the engine and pick-up points for your choice of subframe