First make sure your CLOD install is updated to the newest stock version through Steam. Then go >HERE< to download all the parts that you will need to install. Now go >HERE< and carefully follow all the directions in the post and videos. That will get you up to TF 4.0. You simply install 4.3 and 4.312 in the same manner that you did for 3.0 and 3.01, per the instructions in that post.
To be on the safe side, I would delete the cache folder in the "...\Documents\1C SoftClub\il-2 sturmovik cliffs of dover - MOD" folder, before launching the game for every version during the process to make sure each step is working.