if you keep your old BD controller board and just connect it to a new drive i believe it should just work. if you think the BD card is faulty and have to replace the full unit. then yes it has to be remarried. but yes it can be done. i think you would need to be on 3.55 to do it though, as i dont think the tools work in 4.xx. i could be wrong though. things change fast lately with ps3.
look in the forum for ps3 downgrading and brick fixing , Racer is smart he'll be able to aim you in right direction of files needed etc.