The short answer is yes, you can fit them, likely with a spacer depending on where u want to mout them.
Can you list out the current equipment you have
@Ctheodores...that makes a diff in what you might want to run.
Depending on what you have, M vs MX would dictate the best fit.
I actually have substantial input from Odin
@Earmark Marine on my final system (sold me everything but my subs and sub amp, killer deal btw) and thats after countless emails/call/pics with JL Tech support to get it dialed in.
To me, if your only running a single pair of M770s in the cockpit and the rest are MX650s its not worth it as much, esp if you cant throw a good amount of power to them.
Once we know what you got, can fig out best route.
I did my sytem in 3 phases, as I learned more was able to zero in on exactly how to get it to my liking.
How do you listen to your music, type...that also helps.
I have swivel clamps and the remote knobs to help me adjust on the fly...all come in handy.