Any one ever replace caps or modify there Xovers

UH? Can't you just LOOK at it and draw the Sketch-o-matic?
The DCR for the inductor can be measured.....amp off and lift one leg.
The problem would be the inductor value. That, too, can be measured.

Start tracing wires.....and maybe take a few photos.

Might be a dumb question..but is the schematic absolutely necessary? Couldn't you just replace the old 10 uF cap with a better 10 uF cap and not have any issues?

I am with Magfan and Fishboat. It is worth trying if you really like your speakers, they'll never be Nautilus though.

In two Focal threads, member "johnsonwu" comments about the benefits of replacing original equipment x-over caps with higher quality caps… but some members said that wasn’t such a good idea … which I think "4est" is saying in his comment “they'll never be Nautilus though".

Are you guys saying higher quality caps will only change the sound of the speakers for the better?

There are many options before replacing caps. Dampening materials, coating drivers with dope to make them stifffer, using dynamat (spelling) on the driver baskets and x-overs inside the cabs, and polyfil inside the cabs. Very inexpensive and worth while. Caps are caps, each has a benefit and each has a negative. 10uf caps can get up there in price and the sizes vary significantly. Mundorf oils are cha-ching $$$$$. The benefits to me are slight when compared to other options. Finding a better componemt that mates with your speakers is much more beneficial. For instance, try a preamp that is designed as direct heated or transformer coupled. I would be that the improvement realized with this would be five to ten times better then replacing caps. You should also take a listen to different speakers. Go hear the Nola Metros for example.

Happy Listening.