Back to you Georgie boy. Any of your arguments I see as null and void my friend with the fact your looking at an engine swap. The word practicality comes into mind with toughness. Have a look at any comp seen most are gq's. yes they use gu diffs but the only difference here is cv joint size the rest is still all the same. A GQ is tougher straight of the box hence why myself and mud runner own both. The GQ for the hard and rough and the GU for the comfortable touring.
Back to your engine swap. You will certainly be making the car weaker if you choose the Chev route while bolt parts and aftermarket is great, their longevity and reliability isn't great compared to that of a well maintained Nissan donk. As for your suspension worries show me any decent drag, race or street car that doesn't have some form o modified suspension.
As for the the earlier remarks about rocky track, if you can't get up this in a standard gu ( maybe a 2" lift as most are these days) then you should put a for sale sign on it straight up.
Bring on September I say
