Installing a 3.55 Firmware won't do the trick, you'll need NOTHEROS.PUP (install using recovery mode), a 3.55 CFW that will skip RSOD then install a pkg fix. After that you can install any FW of your choice.
What you have to do is make sure the ps3 is on 3.55. If it is not go through the downgrade. Once it is then install the nothers.pup from the recovery menu. Once the ps3 boots up again install the package. Once that is done install what ver firmware you want. Thanks