Not really any. But you cant use the L67 windage tray/gasket without modifying it to clear the oil-pick up. The L26 has a built in (so to say) windage tray in the oil pan, and doesnt use any gasket, just rtv to seal it to the block.
(Since we're both building L26's no need to change out pans, just grind a few spots on the L26's oil pan, and it'll squeeze in our cars.
Also, the l26's is MUCH thicker and heavier. If I dropped it, I wouldnt be afraid of it denting..whereas the L67s is a very thin pan, that does dent easily.