If you need to open the top cover on K2+, for a better visibility or for a ventilation (when you prints PETG), you need to remove CFS from the top first, or use a CFS riser.

Also when you wants to print with TPU you need to install the spool right above the head for direct input.

This model for two CFSes installed on top of K2+, bottom is on sliding rails.

Riser is rigid and hard fixed on K2+ (by holes on the top rear, just remove the rubber caps). And with a TPU spool holder (may be installed under the bottom CFS).

For a spool holder i'm using (useless) K2+ side spool holder, unbends existed filament guide (see pictures).

Distance between CFS foot holders must be 200mm, side shift up to you (on pictures top 55mm, bottom 32,5mm, this is centers). All dimensions by the aluminium profile.

Assembly using rubber-tipped hammer. You will hear dull sound when the profile reached the end.

Other parts to build:

1) V-slot 2020 aluminium profile 450mm - 3pcs

2) V-slot 2020 aluminium profile 388mm - 6pcs

3) Sliding rails H45 450mm - 1pair (i'm using FGV (Formenti & Giovenzana) Comfy 145 SlowMotion 54.5145.C7.40X.00, but you can use almost any 400x45x12mm rails, it all have standard dimensions)

4) M4 8mm screw - 38pcs (i'm using DIN 7380 black color)

5) M4 5mm screw - 18pcs (for rails; i'm using countersink head, white, but possible any type)

6) M4 t-nut - 44pcs (for V2020)

7) M4 5mm heat-set threaded insert - 6pcs (for sliding supports)

8) Rubber pads 20*20*2mm 6pcs (i'm using Space Pi rubber pads after CFS mod)

Pictures coming soon, printing...