I put 99-00 SI rear disks on my 98 EX about 6 months ago. I bought the front & rear brakes with the rear sway bar and a 7/8" master cylinder for $300.
The hardest part of the whole thing was reaching the the little bolts holding the clamps for the E brake cables.
I would suggest bleeding the s**t out of your brake lines to make sure there is no air in there at all.... and especially if you change the proportioning valve during the swap. I had to bleed my at least three times before getting it right.
If you have an EK and plan on changing the proporitoning valve, get the one for a 99-00 SI for the easiest swap. I did and the part bolted up in like 5 minutes with no modification needed whatsoever. The Integra proportioning valves may work but
the ones I've seen pictures of on the internet don't look the same at all.
I went with the SI valve because brakes are the one thing I don't want to f**k up.
Here some links I've saved from my research before the swap. There's tons of s**t out there man.
<< is your friend
civicland 6th gen brake swap
Knology Civic Brake Info
HAZone 6th Gen Civic Rear Disc Swap
Swap your Drums for Si Discs
HybridGarage 5G Rear Disk Brake Swap
The Brake Bible