I currently have "clean" install, UP2, UP3 and HSFX all installed (actually all in all 7 separate installs
). It's all safe, just keep the installs separate and in good order. The method I use is to have a postfix on all of the installs, and the just remove the postfix from the install I want to use. As in, my install-in-use -folder is "Il-2 1946" and the ones that aren't have some postfix like: "Il-2 1946 UP2" for example.
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