Any one ever replace caps or modify there Xovers

Yes, caps AND inductors. In my Infinity RSIIa.
It was a fun thing to do.
And you MUST have the schematic for the crossover or forget it.
It was very hard to aquire mine back when, and now it would be impossible, unless someone happened to save them. Infinity changed hands, and the dude who gave them to me is long retired.
You would have to ask B&W...?? or find someone who has the schematic for your crossover.

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?