That is a fallacious comparison.
An amp is even labeled “ no user repairable components inside”
I mean no disrespect: but you did not take advise from an expert.
This places you in no position to give advice.
Also you seem to not comprehend that there is no easy access to luthiers where the OP is located!
Could a luthier do a better job? POSSIBLY.
This is not black magic: it’s mechanical fitment with documented tolerance and methods: MOST of the vids CONCUR on these aspects.
I AM an expert. I have built thousands of instruments. Setup many more than that.
I am a really good luthier, with more than 4 decades experience.
Nut filing is easy peasy when going slow and measuring carefully.
GOOD CHOICE to get the right tools: being a mechanic’s offspring it’s like removing a nut can be achieved using pliers, but a correctly sized spanner, box end, or socket is far better.
Replacing a nut is only slightly more difficult. ( if you botch it) and in a pinch, there is a well documented CA glue and baking soda trick to fill the slot back up.
From the factory nuts are almost always cut too shallow (too high from the fret)
As the “factory action” ( relief and saddle height) is almost always likewise too high.
Key takeaway!
Go slow and when it is ALMOST LOW ENOUGH, STOP!
That one extra stroke could likely be too much, and the nut is toast.
Hand cut brass nut: for one example. (Needed a polish, this was the test assembly) zoom in on the below pic: after you get the slot to depth, shave the TOP of the nut so that the string stands proud of the top of the nut a bit.
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The rest of that bass
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started as a Squier D5 with a snapped headstock. Replaced the neck with a flamed maple neck, canarywood fretboard.
Treated the maple shaft with AquaFortis (traditional chemical staining that uses heat to react with the tannins in the wood rather than pigments)
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