Replacing a stereo in a '98 Nissan Micra

First time poster in the motor section so don't eat me alive for being an ignorant fool please, it's a question about a micra anyway so it would be a tasteless endeavor for those of you tempted.

Got a pioneer cd player/stereo for the micra knowing it probably wouldn't just slot in easily, the Nissan ISO cable are obviously fairly old and although the connections look quite similar they ain't going to fit.

My options are:

1. Take apart the pioneer connections and wire the stereo up with the connections from the original stereo (problem there is I won't be able to bring the stereo back then if I make a balls of it)

2. Try and replace the in car connections with some store bought ones although I don't know where I get them. Don't want to make a mess of that either.

3. Bring it to a Nissan dealership near my gaf but they said it would cost 90 euro to fit it, which seems laughable as that's how much the cd player itself cost.

4. Bring it elsewhere, suggestions?

Have no experience soldering and a basic knowledge of inline splices with fairly basic things like bike speedometers but would presume it's a straight forward enough process I just haven't been able to find an online tutorial.

Any ideas?