ZJ rear disc question

well, i've got the parts but i've got some quick questions. it's my first rig and i've done a lot to it but i have yet to tear into the rear axle or do any brake work besides pads/rotors. are the calipers for the rear discs side specific? i've read in the write ups that the soft lines point down. mine appear to point upward. i'm just wondering if it matters which side the calipers are mounted on. also, is it going to be obvious if my wheel bearing seals are shot? i'm guessing most people will just say replace it while you've got it apart. i dont have a whole lot of time to do the project and i read something about needing a slide hammer. are they that difficult to change? also, back to side specific mounting of the calipers, one thing i noticed is the bleeder valve location. it differs depending on which side the calipers are on. i'm assuming since their purpose is to let air out, i want to mount the calipers on the side which will put the bleeder valve as high as possible...
Jut looking for some clarification before i tear into in the snow tomorrow. yay

Yes, bleeder valves on top.

I'm having gears installed on my 94 axle this weekend, but today I installed the longer lug studs(from 96 2wd f150 front) and yesterday I installed the ebrake hardware on the backing plates. It's probably gonna total around $200 for the whole ZJ disc swap.

Well worth it too!

X2 Well worth it!!!
The caliper brackets should have L and R marked on them, and yes, bleeders on the top of the calipers.
My ZJ conversion simply put...
Calipers on back side of axle, hoses point up, bleeders at top.
To remove bearings/seals, yes slide hammer, the bearing should take the seal out when it comes free of the axle tube.
I used a block of hardwood to carefully and squarely tap in the new bearing then seal. I put a bead of RTV on outer part of my seal to ensure no leakage.
Yes, install longer studs as gradon advises.
You will have to get creative in finding a solid way to mount the hose and line to the axle. Depending on the year, you may have to change out the proportioning valve and/or booster/master cylendar.
Total conversion will require some adjusting, grinding, beer drinking. I am happy with mine. stops straight, level and solid.

I can't wait to slam on brakes for the first time with the WJ brakes up fron ZJ in the rear with the 03 WJ master, booster, and prop valve. It obviously feels like the brakes on my girls 02 WJ. But since I still haven't installed my tie rod it's sorta hard to steer up to speed.