On our '18 Tahoe, those metal lines are for the rear heat, I believe. They tee off the
plastic tees for the heater lines going into the firewall of the truck. It looks like there is a clip for those lines down about where the firewall bends into the floor panel of the truck.
Watching the video attached above, I would suspect that you can probably get that cover off without bending the metal lines, but if you can't, you may want to see if you can detach the metal lines down at the bottom of the firewall to see if it gives you any extra wiggle room. You'll also want to loosen the heater hoses from the clip the author of that video shows, to help give you more room.
If your vehicle has a fair amount of miles on it, you might want to invest in replacement heater hoses, which should include those tees, in case they're brittle and you break them when trying to R&R the cover. I'm not certain I found the right parts in the online parts lookups, there seem to be a fair number of parts not listed that are in the diagrams, but it looks like the replacement heater hoses may be about $100 US total. Worth the investment, to me.
Man, I really don't think I have OCD, but I'd DEFINITELY have cleaned those covers before reinstalling them!!
Actually, I'd have removed them and thrown them in the spares pile in our shop!!