yea, back to your trip to Nordkapp, Rail Pass cannot be used after Bodo because the train line ends in Bodo, you will then need to take a coach or ferry to travel further north~
you may also consider flying to Alta or Honningsvag (by SAS or Braathens), domestic flights are cheap in Norway~
but HOLD ON.... since the whole idea of you travelling north is to see the midnight sun and the northern light, I've done a search for you:-
There is midnight sun north of the arctic circle only, the arcticle circle crosses Norway a bit south of Bodø (at Saltfjellet mountain pass). The further north, the longer the midnight sun period. There is absolutly no need to go further north than Bodø/Loftoen to see the midnight sun.
Midnight sun periods in some Northern Norway places:
so please re-consider if you're really heading to Nordkapp cuz it's really a long looooooooong route & definitely no single direct coach for arrival. you'll need to transfer many coaches for manyyyyyyyyyyy times, traffic costs are multiples that I can't calculate.......