Drilling the fork is relatively easy, though it's difficult to counterbore the back end so the hut sits flush. I don't like drilling the rear because the clearance issues means I have to drill from an angle. Also if the bridge isn;t designed and properly reinforced for the recessed nut design it cn create new complications.

My suggestion which depends on the bolts being long enough.

1- mount the front brake in the rear with a conventional nut.
2- buy a 1" long recessed nut and a 6x1 Stainless cap screw about 1" long (measure everything) to know what you'll need. Cut the head off the recessed nut to make a threaded connector, then mount the rear brake in front, reach through the bottom of the fork and position the connector on the bolt and spin it on as far as possible. Then finish the job with the cap screw.

Of course all this depends on some serendipity, but I've had success with the method a number of times. If it's practical for your bike it's the easiest approach, with zero risk of complications or damage, except for the few dollars spent on the hardware.