So there are a few modifications to various bits.1. The y-tensioner is my own devising, although I subsequently found others very similar.2. I also made the bearing holders for the y-axis, I found I didn't have enough clearance without them.3. I use the M3 thumbwheels to level the heated bed.  4. For the x-tensioner I used an M3 bolt with two small bearings and washers no guides for the belt.5. For groups of cables I used braided sleeving which kept things clean. I used to use cable chains but found they were too noisy in printing. Also I found running the cable underneath the ramps board kept things relatively neat.6. I now use a e3d v6 hotend and with a bit of persuasion it fit into the extruder, I may end up replacing this if it causes me issues.7. While we're on the extruder I reworked the smaller gear to move the nut further towards the motor shaft (maybe a little too close) and closer to the gear so it's on the flat of the shaft. Heat up the M3 nut and insert into the slot and then use an m3 grub screw to attach it the shaft. I found the fit was so tight I had to fit the small gear to the shaft with a G clamp and a little care.8. For the x-tensioner I used an M6x50 coach bolt I had and just ground the head off until it would fit into the x-idler end. On the outside I put two nuts (one in the block, one for locking off) and put a slot in the end of the bolt with a dremel to tighten the belt.9. Finally found the z-coupling I used. As part of the "Adapto" printer.Based on:https://www.youmagine.com/designs/i3-y-idler-with-tensioneri3 y-idler with tensioner (by me)https://www.youmagine.com/designs/yet-another-i3-spool-mountYet another i3 spool mount (also by me)https://www.youmagine.com/designs/cable-strain-relief-for-i3Cable strain relief for i3 (still by me)https://www.thingiverse.com/thing:291291Prusa i3 Rework Extruder Ugrade (by mrice)http://www.thingiverse.com/thing:371842Prusa i3 Hephestos (by bqLabs)http://www.thingiverse.com/thing:16428Just another M3 Thumbwheel! (by julianh72)http://www.thingiverse.com/thing:85809i3 reinforced y-motor (by xoan) - I've modified this to increase the corner resolutionhttp://reprap.org/wiki/AdaptoAdapto (by ROTORIT)https://github.com/josefprusa/Prusa3-vanillaBelt-guides used (by Josef Prusa)https://www.youmagine.com/designs/i3-frame-stabilizer-15-35-degreesi3 frame stabilizer (by me once more)