SirPaperbag

The part about needing new trailing arms is 100% correct, as the drum brake ones lack the proper mounting points for a disc brake system.
But you've got to be careful with which arms you choose, as the wrong ones could end up increasing your rear trackwidth and that's gonna end badly for your handling.
 
As our M-chassis have borrowed a lot of suspension components from 5th gen Civics (EG), I'd recommend searching for EG5/EG6/etc. trailing arms, as they should keep everything in spec. I for one got a pair of EG5 arms to go with my non-ABS system.
 
But that's only part of the problem.
 
If you've somehow managed to get yourself the right trailing arms then you still have to find a matching brake proportioning valve (or prop valve) that splits the pressure correctly between front and rear.
Otherwise your rear brakes might either not bite enough, or bite too much and cause the rear to kick out while braking (very dangerous).
This is especially important if you've got something like an MOT or TÜV here in Germany, where your car gets an inspection every X years and they check your brake performance.
 
M-chassis Civics also use an old style of prop valve, which makes it EVEN HARDER to find the correct ones. What you generally want to get is called a "4040" valve, which is just the model number, nothing more (some dumbasses online claimed those valves split 40/40, but where the hell would the remaining 20% go?)
 
I also found a nifty table somewhere on an obscure forum, and I don't know where exactly I got it from, so I sadly can't attribute the original poster, but here it is:
 

 
 
And depending on the caliper sizing, you might even have to upgrade your master cylinder, but that's getting really technical.
So, in short, get the correct trailing arms, a somewhat correct prop valve and maybe upgrade your master cylinder.
If you want to do it properly, it's a whole lot more work than just doing enough for it to work.
 
 
Pro Tip: You can also fine-tune your front/rear balance by using more or less aggressive pads.
 
 
And regarding rear ARBs, you've got a choice between either buying some used EG6 brackets, using aftermarket ones, and reinforcement braces with mounts included.
 
I went with a used EG6 ARB, plus mounting hardware, because I wanted to try out how much difference just that dingy little thing would make (a lot).
 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Here are a few pics of it both installed, and some pics of the used mounting hardware. You also need fitting lower control arms with mounting holes for the endlinks.
And I'd recommend buying new endlinks while you're at it. And maybe a few harder rubber bushings on top.
I also had to fabricate some small metal standoffs for the mounting bracket to properly fit to the rear frame (top right picture, the screw just above the yellow marking).
 
This would be the alternative, a rear brace with mounts included:
 

 
But some places also carry aftermarket versions of the OG hardware that I mentioned and shower earlier, so that's an option, as well.
 
All in all, it's a s**t job with tons of little hang-ups, researching, browsing marketplaces and painful installation, but the handling difference is night and day.