New wasteboard ala transfer punch,1/2" Forstner bit and can’t remember think #9 drill bit. Mounted, then drilled using the XXL for 2", 3" and 4" T-track spacing. Mounted T-track using #8x3/4" Phillips pan head screws. The T-track came from www.orangealuminum.com the cheapest I’ve seen and pre-drilled at 3" spacing, easy to work with. Yes, 1/4"x20 bolts slide over the pan head screws just fine, I didn’t need to countersink them. Yes I left space at the front of the machine to get 1/4"x20 bolts into the T-track, about 3/4" from the from plate. Next step is to cut MDF strips to go in between, then tramflat. To answer earlier questions, I didn’t put a DI on my Z-axis as planned (got lazy and didn’t want to disassemble the machine), but laying all of the T-track out I saw little to no gap under the 36" spans, it’s pretty flat, unless of course my T-track has a VERY consistent warp that matches the bed warp. Drilled the holes using the XXL with a 0.0625" end mill at 1/4" deep. I used CC and set my hole radius at 0.032" and did pockets, worked great!
Dan