Ampacities of cables is dependent on both the insulation type and and the environment they will be operating in. That said, 4/0 cable should be good for at least 300 amps in most environments and 1/0 should be good for roughly 200 amps. 2/0 will be in between. Those are ball park, only.
If you choose to parallel them on a bus like NewBlackDak is suggesting, I'd go with the 4/0. That would give you a good and safe installation. If you go with a terminal block, the 2/0 should be plenty adequate. You would be talking about a lot more connectors and what I would think would be a bit of a cluttered installation using the terminal blocks. But it would surely work.
I would say that you should connect them in a manner that won't be overly difficult, and I wouldn't stress about cable lengths. Make it easy on yourself. Make it a "clean" installation. You'll be fine, either way. Whatever you do, remember that the installation of the lugs on the ends of the cables will be your most critical concern. Make sure that is done right!
Jim & Angie, Boise, ID
2021 Entegra Esteem 27U
2017 GMC Acadia Denali