Mixed bag
Well Nick, you have a mixed bag there.
The best of it is the Haffler gear. That is comparable to current gear.
The NAD tuner is a good one. It will need a good antenna, preferably a roof antenna.
The cassette deck was a middle of the road unit. Cassette tape is really a dead medium. Do you plan to use it?
The CD player will sound fine, but it is of a generation that will not play CD R or CD RW.
The speakers are the most problematic. Since the Hafflers were bridged, I think they must have been driving the Polks, which I think were four ohm, but I can't remember for certain. The cover that goes over the tweeter and crossover is missing.
The infinity speakers I think will be inferior to the Polk speakers, but you might want to give both a listen. The Polk is one of their first offerings, if not the first offering from Polk. The Peerless tweeter is time aligned. There are two mass/mids and an ABR. (Passive radiator)
Now the speakers will be considerably inferior to modern offerings.
So to hook up.
The tuner in the US and Canada should have the switch set to 75 micro sec.
Connect the antenna to the appropriate input. Coax to the coax connector. If is flat cable to the 300 ohm. Connect the left and right outputs to the preamp tuner input.
If you plan to use the cassette deck connect tape out to tape in on the preamp and tape in to tape out on the preamp. Use the tape 1 inputs and outputs
Connect the CD outputs to AUX input on the preamp.
Now connect the pre amp outputs to the input of the amps, one for each channel.
Now the speakers. The amps are bridged, so connect NOTHING to the black negative terminals. If you do you will blow it instantly.
One red is positive and the other red negative. It does not matter which, and I can't tell you. Just make sure you connect the same terminal on each amp to a positive on a speaker and the same terminal on each amp to a negative on a speaker.
Check all connections. If everything is OK, plug in, switch on and see what happens.