Upgrading a client from 4.05 to 2015 with a stop at 4.3 due to ACS Property Management requirement. 4.05 is MAS 200. I'm trying to install 4.3 MAS 90 on top of the 4.05 MAS 200, and am getting stopped because I'm installing 90 over 200. I tried renaming the Uninstall Information folder, but that's not resolving the problem. Anyone know/remember how to do this? According to the 4.3 install guide, parallel migration is not an option.