You can slide this intake in your filament roll, that it doesn´t wiggle on the much too small standard spool holder. At the ends you have to put one bearing at each side. I used "608ZZ 8 x 22 x 7 mm Deep Groove Ball Bearing" you can get these on amazon very cheap.
This Intake works with filament rolls which have an inner diameter of 52mm. For example the "HATCHBOX PLA 3D Printer Filament, Dimensional Accuracy +/- 0.03 mm, 1 kg Spool, 1.75 mm, Black" on amazon.
The spool Holder mounts at the upper rail with the regular M5 screws holding the frame. That way it feeds very good to the feeder under it.
The two knobs just stick into each bearing and then the spool is just placed on the spool holder.
Especially the spool holder needs support. I put it with one side to the bed. I would also recommend using support on the other parts. Only the knobs don´t need any support. I printed with 20% infill, the knobs with 80% infill. I used also black Hatchbox PLA and printed it 200 Degrees, bed on 65 Degrees in the beginning, lowering down to 55 Degrees.
I really like this "Wood" PLA. its very rigid and feels like real wood.