This is the result of my frustration over not being able to find a decent tilting extruder system. Introducing: the Echelon TV6.
This is designed such that when you have two E3D V6 hotends with the same nozzle, a 45° tilt of an MG996 (or similar) servo will result in the inactive hotend swinging down into the exact position of the previously active hotend, eliminating all need to fiddle with offsets for each nozzle. There is also only 1 part cooling fan needed for this design, which I have designed for a 5015 radial fan to reduce the size of the overall assembly.
You will need 2 E3D V6 hotends (or clones), a MG995/MG996/MG996R servo, and a 608 skate bearing to assemble this, the rest of the parts are ether glued or bolted together.
Note that to stop oozing from the inactive hotend during dual-material prints, you will need to install metal flanges to block the nozzles when in the retracted position.
This is an untested work in progress, proceed at your own risk.
EDIT: Upon review of the design, this will not fit on the X5S due to the servo position. A reworked version to correct this is in progress.
EDIT 2: I have uploaded a revised design that re-positions the servo, however this does use a mechanical linkage which could lead to very slight inaccuracies. For this revision, you will need to print the files marked "Rev1" in addition to the "Hotend Clamp", "Tilt Assembly Front", and 2 "Pins". You will need an additional 2 M4 bolts for the linkage, as well as two 608 bearings for the tilt assembly.
I am leaving the original files in place for anyone who prefers the original to the revised version.