You seem to lack faith
It wouldn't be a permanent installation for sure, but it's enough for testing.
What I have in mind is something like this:
but for testing I would try something like this mated to the EFI lower manifold, and throttle bodies instead of plenum chambers like in the picture.
I don't know how much clearance there is under the bonnet and what would be the optimal length for the intake runners, so I wouldn't want a setup like this if runners would need more length than what's available - they wouldn't fit!
So maybe short stubs and then length of silicone tubing and perhaps a throttle body over each rocker cover in horizontal position or maybe a custom made aluminum one... like this:
