Wow those are very old releases. The current version is 6.2.3.4.
In all cases, you must upgrade the managing FireSIGHT (known as Firepower Management Center since release 6.0) first since it has to be at or above the release level of any managed devices.
Once you get the FMC to 6.1, you must also bring your managed devices to that release because moving up to 6.2 means the oldest compatible managed device release is 6.1 at that point.