Longer "y" axis

Im looking to extend my Y axis so that I can flatten live edge slab then carve on before joining to make live edge tables. I planning to Keep the onefinty X and Z axis the way they are. Im leaning toward the rack and pinion setup like AVID CNC on 2600mm long square linear rails, but haven’t ruled out ball screws. Basically I would be replace the two round Y rails and Ballscrews that 32" on each side with 2600mm long linear rails that are mounted every 12’s. Im still planning on using two Y motors. Has anyone done this yet? If so where did you get your rails? I have found some but not sure how good they are?