Made a little progress last night.
I used wire ferrules and a crimp tool to make the connections for the push-down connectors on the crossovers and the amp outputs. Color-coded shrink tubing for + and -.
The Alpine amp uses these strange connections. You insert the wires into the housing and then there is a 1.5mm allen on each side that cranks down and tightens the wire ends in place. I've always thought the diagram on the amp leaves a lot to be desired. The connector is not keyed so it's easy to accidentally swap + and -. The connector plugs in vertically and the + and - symbols above each connection point on the amp reads left to right. Brilliant! No opportunity for error there.
Finished all the amp output wires. Wrapped each wire in tech flex. Zip-tied the bundle in place temporarily while work on the rest. I'll tidy up the whole thing once I finish the output wires and the lead for the remote.