Make a diagram, and take all of those measurements. When we replaced the jackknife with recliners, I used the original sofa measurements to narrow down the choice of replacements.
For example, the old one was 53" so I knew a 72" wide set of recliners wasn't going in there.
Then pick out your replacement and read the installation instructions. It should have measurements and clearances (if you need them). Then you head back out and see if it'll work.
Our recliners needed 2 or 3" of space between the wall and the back of the seat. The jackknife measurements didn't apply, so I had to go back out to the RV and cut up some cardboard templates to see if things would work.
Final piece of advice - buy from some place where you can easily return them, if they don't work out.