Anything is doable -- but whether it is wise or recommended may be another question entirely. You will want to read through the Rusted A-pillar
https://www.expeditionforum.com/threads/rusted-a-pillar.58986/ post and consider whether there may be any structural drain-path differences between the structure of vehicles with factory sunroofs and those without (I don't know, and I don't know whether anything other than the original design logs would be conclusive on the question)
Good luck if you attempt it. As for me, after 12 years of non-leaking, and 8 years of fighting leaking sunroofs on my 2nd gen EB 4x4 expedition, I know I'd not buy another. (at the time the EB came with it, plus the full kids DVD entertainment package - that was on the wife's must have list with kids of 6, 3 and newborn at the time...)
As the pictures and description in the linked thread makes clear, the drains are integrated into the body with the actual rubber drain tube draining behind panels with openings to allow the water to exit the vehicle through the bottom of the panels. I've yet to find a good routing diagram for the four corner-drains exiting from the sunroof itself. The thread makes clear the front drains route through the A-pillars and the rears through the C-pillars. Doing that with anything less than a full frame-up build may be an exercise in futility. But I'm older and more conservative now.
45 years ago it was nothing to turn cars with automatic transmissions in 4-speeds street rods, big-blocks to small-block swaps, steel cranks, custom ground cams, port and polish and port-matching on intake/heads, tunnel rams, etc.. All the things gear-head teenagers thought about and could afford when a $5 bill could cover an oil change with filter, and a $10 bill could cover 8 plugs, a cap, rotor and 2 sets of points for the dual-point distributors. (individual points dwell of 26 deg, combined for 32 deg) `

` Funny what stays locked away in memory forever....