Thanks guys, I find your input really helpful! Thank you Lonny for the exstensive posts with instructions to get me through the finishing stage, I appreciate that!
The first coat after sanding (on the top of the headstock only) didn't hide the witness lines completely, but only made them less clear. Furthermore, the finish on that part of the neck now varies from dull to high gloss per cm2... it doesn't look good now. But I hope another layer tonight will make things better.
What I will try is to get the neck looking good again by applying some new layers.
The body has 7 layers on there. It starts to level out throughout the consecutive layers applied. That means I will probably buy a new can and apply three more layers. If I'm with ten, I start to wax with steel wool as Lonny described.
I hope it all works out, but I'm not feeling to well about it. At least I got some great advice here! I'll keep you posted. And once it starts going somewhere again, I'll add in some pics too

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