(adsbygoogle = window.adsbygoogle || []).push({}); Or can someone send me to a trusted website.

No you can not.

You can only use a Cobra ODE

No you can not downgrade

The lowest firmware a 3001a/b can get down to is 3.56 just one update above the magical 3.55...but it will let you install ode allowing you to be able to make n play backups from internal or external but this will require soldering and a expert skills.