Connecting to vent pipe from weird angle

[krubinow]

I'm building a laundry room on the top floor of my house. I have the vent pipe already run up into the attic where it's "poking through" the top plate by about 6 or 7 inches. About 4 or 5 feet away is an existing vent (from another part of the house) that goes right up through the roof. I need to connect the new laundry room vent into this, but it's not at a nice 90- or 45-degree angle from one another (see picture and drawing). Can anyone recommend the best way to connect the new vent into the existing vertical one? My thought was to go horizontally (upward slope) from the pipe sticking up along the attic floor (which will make it easy to support it) and then 45 up into a wye that I'd put on the existing vertical vent, or go along the attic floor, then 90 up, then 90 across horizontally into the vertical vent with an upside-down sanitary tee.
For connecting the PVC to ABS, I bought Fernco couplings (P1056-22) to join the pipes.

 

[Sylvan]

I never used an unshielded coupling, as some codes call it a violation

 

[Sponsor]

 

[Reach4]

For connecting the PVC to ABS, I bought Fernco couplings (P1056-22) to join the pipes.

Fernco 3000-22 or P3000-22 is the shielded version. Readily available, and almost as easy to use as unshielded would be.