Hook up questison

Since the NAK receiver doesn't have pre-in/main-out jumpers
you can't hook it and the NAD integrated amp together. It
can really only be used as a stand alone unit.

You could run the tape out of the NAK into the tuner input of
the NAD and use the AM/FM tuner section of the NAK. This
would mean you would use the NAD as the main amp and preamp.

The NAD does have the jumpers, so later you could use it as
either a preamp or as an amp, if you remove the jumpers.

"Does this mean I use the tuner portion of the NAK only then plug everything else into the NAD?"

Yes.

I agree with Swamp. Try both as stand alone units and see which sounds better.

I was a Nakamichi and NAD dealer and sold both of these units. The NAK should be a little sweeter, smoother and warmer in sound than the NAD, but the NAD will be a little more powerful and dynamic and have better bass control.

You'll just need to see which one is more to your liking and which has more synergy with the Pioneer speakers.

Let your ears decide.