Maple boards are usually smooth enough straight out of the box however if you think it needs something this is one of the rare times i would use 0000 steel wool. Just need to have a strong magnet handy to sweep over the whole neck & board to pick up all the small steel wool fibres left behind to prevent that ending up in the finish.
About 6 coats might be enough and then leave for a couple of weeks to harden up.
Need to buy some of those fretboard protectors which i think are on PBG store site and carefully use 0000 steel wool again to remove finish from frets. Best to do this with neck not attached to body as you don't want any of the steel wool fibres getting anywhere near your electronics.
Cheers, Waz

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