Hi there, unfortunately, software re-imaging is only possible for the lower end 5500-X models (5515-X through 5555-X).
For the 5585-X series, a hardware refresh is needed. You will need to replace the CX blades with Sourcefire specific blades.
There are upgrade bundles that make the process a bit easier For instance, if you have 5585-40 then you will need to purchase an upgrade bundle:
ASA5585-40-FP-UPG
That will include the free "Control" license, hardware, smartnet, Sourcefire subscription and FireSIGHT management center options.
I hope this helps!
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