Jantzen Wax Coil or Mundorf M-Coil CFC

You should be fine with the Mundorf honestly.

If the wait was say a month, that would be a different thing, but a year is unreasonable.

The 70mm foil should be perfect for your application, just make sure to also upgrade the wiring on the inside of the speakers.

We can upgrade the tweeter and woofer wiring easily enough. The midrange is made up of 14 forward firing tweeters on each cabinet, 28 in total, and a harness of some kind. Also, they may be in an enclosure, don’t know. There is a rear firing tweeter and mid also, but I am not concerned about that. I am considering whether to upgrade the wire for the woofer and tweeter drivers, but not the mids. If unpleasant, go back to stock.  I have Cardas Clear Beyond speaker cables and access to synergistic Cardas hookup wire with similar geometry.  The hookup wire was used in later model Merlin speakers and was also part of an upgrade package.

My USB and XLR cables are DIY copper foil. 

Speaker cables are 12 gauge Neotech Solid OCC Copper DIY

Internal cables, including crossover are 14 Gauge Neotech Solid OCC copper

Once you build your crossover, just try out a few different ones, see what sounds best in your application. Every speaker is different. 

Must be a tad tricky soldering foil type conductors to those mini usb solder tabs! 

@grannyring My dac doesn’t use the Power and Ground connectors.

It was hard at first, but I have gotten very good at it :) The trick is in the fold at the very ends.   

I use 16 gauge Mundorf foil for my cables. 17mm wide.

And yes, they sound incredible.