help!! DWV questions

i'm replacing two 3" floor drains. one to the upstairs bathroom/vent, the other to the downstairs laundry/utility sink.

my question is can i lay the vertical pipe all the way to the footing, so when it rises out of the floor, it will be flush with the wall/footing and i can frame around it after? or is that really bad? it's a full size canadian basement btw. deep enough so nothing freezes

the reason i'm asking is the old system doesn't look right. the risers out of the floor are further from the basement wall than the drain coming down from the sink. i don't know if this is on purpose to keep the pipe away from the footing or leave room for a wall, or just the limitations of installing metal pipe 50 years ago

should i just do it the same way? or can i lay the pipe closer to the wall like i want? i figure if i do that, i can eliminate an elbow. it also seems to me that that i can align all the fittings for the waste to take the shortest route, rather than first away from the wall, then towards the main drain

some houses i've seen around here people frame a little box around the cleanout. to me it looks ugly and seems i could just as easily put a little door in the wall after or just break thru the drywall if i ever need to get to that cleanout.

would help to see a picture of a proper setup since none of the books and sites i've looked at cover these details.

also not sure on where to reduce the line. figure i can use a 90" elbow on the end of my 3" main, then the reducer on the end of that elbow so it rises out of the cement, then a Y with a cleanout and plug the sink into there.

i'll have a digital camera later i'll try and post some pics so everyone can see what i'm talking about

I'm lost post a pic.

http://img119.imageshack.us/img119/1633/dscf05890cv.jpg

this is the old cleanout for the drain from the kitchen sink after i put in some new pipe last year. sorry i don't have better pics but i already smashed the other one out. this is a top view and if you look halfway down from the top of the pic, you can see clearly where the basement floor meets the footing

i want to know if it's OK to lay the new pipe a little closer to the footing, so the riser ends up closer to the basement wall and centred under the vent/kitchen sink.

then instead of having the waste go thru ane elbow and into the side of the new Y, it should go straight into the top, and the cleanout plug would now be in the side.

seems it would look nicer if i could frame the wall around the cleanout and cover it with a little door or something instead of where they were before

some of the other basements i've seen around here, there's little boxes built into the outside wall to hide the cleanouts. i don't know if there's a specific reason for putting the cleanouts here

http://img225.imageshack.us/img225/5763/pipes1pm.png

this is what i'm trying to do. i hope it makes sense.

1.5" pipe carries waste from the sink
Y has a cleanout.
1.5" - 3" adaptor
90 elbow
3" pipe goes to main.


i want to bring the end of the 3" pipe and the 90 elbow, closer, right up to the edge of the footing, so i can bring down the waste from the sink without the little elbow and keep the whole assembly small enough to hide behind the wall after.