Well that’s the easy part getting them at the same height. Move head to the middle of the Build plate, move plate manually up untill it touches the first (lowest) nozzle, loosen set screw on the side of the heatsink which holds the heat break in place of the nozzle which is not touching the build platform and push the ptfe down untill it touches the build plate aswell. Tighten set screw and they are perfectly Level.
The leaking you say is when running a dual print I assume? Turn on wipe and prime tower and the wipe wall around the entire print also helps… Use the bottom low temperature of the filament your using. And DO NOT USE BLACK OR DARK colors… Those are way more prone to leaking and smearing.
Good luck!
Personally I think the dual nozzle colors thing is a gimik that will not work reliably with 2 nozzles that are flopping around at the same time… IDEX is the only decent way to go imho…
Okay thank you for your reply! I will give it a try…
The leaking is also when printing with one nozzle more object at once. But it’s a lot better with lower printtemperature.
Well, after many months, nay years, I’m back on the forum and I’m delighted to see this thread! 
I’ve just ordered a duet wifi and the e3d chimera, which I’m going to combine with two nimble zesties. 
I’ve been yearning to be able to print flexibles and rigid filaments together, and IDEX is just a step too far in doing the mods for this machine. So we’re kind of left with the chimera as the best option, which means nimble zesty seems to be the only way to get a direct drive equivalent with both nozzles.
Very interested to see the issues with designing a mount. It’s not going to be pretty whatever solution we come up with. Obviously I’ll not be able to use what you guys have done, as I’ll have the zesties to deal with, so it’s going to get messy!
Yes, I know the final cost is nearly a new printer, but not quite, and if it works it would be as good as could be without IDEX, which would be a lot more money…
Anyone tried this E3D Chimera Plus on a Vertex 8400 ?
I think im gonna try this thing on: https://www.thingiverse.com/thing:2513201
I think im gonna try to drill out the whole y rod, from z- space (from top off) on the E3D Chimera Plus.
Can anyone guide me through the software/ marlin modifications to make to make this really awesome ?
Greets !