IMO, there's not much benefit to doing a Gen5 swap.
To get the direct injection to work, you'd have to integrate the stock ECU which would be a huge pain in the ass. Waaaay more difficult than splicing in a LS1 harness from a Camaro if even possible.
You can buy a MSD intake manifold that fits these engines and has provisions for port injection. In theory, you could run without the DI and use an aftermarket ECU. Crank/Cam trigger pattern is the same as GenIV, so it wouldn’t be that difficult as long as you didn’t want DI. But you’ve now added a $1600 intake/throttle body to the parts list and a standalone ECU.
The GenV motors have pretty decent flowing cylinder heads, but not markedly better than stock LS3 heads or ported cathedral port heads.
GenV motors also use the same rods as the GenIV/LS3, except for the Z06/ZR-1 which use a factory forged powdered metal rod and forged piston.
The GenV also as VVT and has a fuel pump lobe on the cam that keeps them from being backwards compatible with GenIII/IV engines, so cam selection is much more limited. The stock LT1 pistons are also 11.5:1. Pump gas driving is going to require conservative timing and careful tuning without DI.
I’m not 100% sure if the oil pan bolt pattern has changed, but that is also a concern. I doubt that the new Camaro pans would fit well in an FC/FD without being too low and I
Moral of the story, buy an LS3/T56 Magnum and spend your extra cash on good ancillary parts.
