I replaced a tweeter in my Divas Be's in 2006. Accidentally cracked a tweeter replacing the tiny metal tweeter covers.
The connection between the tweeter and speaker will need to be resoldered, so you should probably practice a bit so you don't get a cold solder joint which could cause future problems. Leads to the tweeter are very small. Would be worth getting a second person to help hold the wires in place while you solder. Also, use hi-quality preferably high-silver content solder.
Also, be careful of the broken tweeter. Flaking Beryllium is toxic. Enough of it in your lungs can lead to permanent breathing problems. Focal will send you a cellophane type material to put over the broken one to contain any flaking beryllium.
Otherwise, two allen bolts and two wingnuts to get to the tweeter. Magnets are strong, so be careful of tools and metal parts laying around. Did mine sitting in place in the theater. Had some help holding the tweeter and leads during soldering. Pretty simple process.
Good Luck. Can e-mail me if you need more information.