Diomedes Dominguez

It should say Step 30 not Step 45.

Jump to step 29 if you don't have the enclosure's back panel.

The second image is for reference only if you are using other fans. For example, if you are using a 4028-fan running at 24V instead of 12V you should put the jumper to the corresponding slot

never assume that you will receive 1 meter of the piano wire, so measure the whole length of it twice, just to ensure the correct position to cut according to your machine. Also, you can give 3 to 5 mm beyond the specified length, it's better that than buying another wire.

vc4_ptfe_guide_upper is in the same bag as the spool holder parts.

On July's video they inform that they wouldn't continue selling the printed parts with pre-mounted inserts.

DO NOT CUT THE EXCESS. Wait for the next chapter to align the gantry, it would be a lot easier in case you put too much tension in one belt .

Can you please point us to the correct step?

yeap, I had to resolve using soldering

RatRig isn't Prusa Research bro, take it easy :D