Definitely likely that I did this wrong. I cut the factory harness off and spliced those wires into the input on the crossover. Then I connected the tweeter to the TW output on the crossover. I didn't connect anything to the other output.
It’s not technically “wrong”, just incomplete. My understanding (and colinl or someone can correct me if I’m wrong) is that the non-B&O system uses passive crossover components at the individual drivers and not any kind of active crossovers that are built into the head unit. So the signal going to the dash tweeter is full-range (vs the rear speakers when the head unit is set to “Driver Focus” and filters the bass from those speakers). So you’re getting the correct signal going to your crossovers and tweeters. However, your woofers are now running full range because they’re not hooked up to the crossovers. This won’t damage them (if it was the opposite and you were running the tweeters full range you COULD damage them), but from a sound quality perspective isn’t ideal. But you should be able to run some new speaker wire from the “Woofer” connection on the crossover to your woofers and you’ll be good to go. Just disconnect the woofer adapters you have on the Focal woofers now and let the OEM woofer wiring sit in the doors unconnected to anything (may want to zip tie it or something to keep it from rattling).
Hmm, I am actually not sure what this would do because another MTC member took apart the Focal RSE-165 crossover and said the woofer (actually midrange, but it's fine) connection was straight through: https://www.mavericktruckclub.com/forum/threads/full-audio-upgrade-complete.21927/post-734301
I just recently installed a component set up front and ran all new wiring for the tweeters. When tweeters are removed, you look in that hole and can't see much because it has plastic in there which obstructs your view completely through but it does allow wires or even the factory tweeter connector to be snaked through it laterally. If you view it upward from under the dash (lying on the floor), there is a TON of room under the dash on both sides. You can reach your hands all the way up to where the tweeter mounts, if I recall correctly. There is room for passive crossover mounting, or even to get arms in and pull wires through. You just can't shove the crossover through the tweeter hole from the top of the dash.
I should have taken a photo now that I think about it, because that amount of access from the underside is nice to have.
