Replacing Floor

Hi everyone!
I’m debating replacing the sub-floor of my 66′ Cortez. From what I remember, and the reason I didn’t do this initially, is that the sub-floor appears to run under the wall panels and get sandwiched/bolted down between the bottom of the walls and the floor frame. Am I right or wrong about this? Has anyone here replaced the sub-floor on their Cortez before? Looking for any tips.
Thanks!