Help with retrieving files from (mac) hard drive I physically removed

This maybe hard as the drive platters maybe damaged by a broken head unit.

I’m assuming you feel/hear the drive spinning so we know the motor is running spinning the platters. Do you feel the head trying to index its self when you power on the drive, you should feel a click as the head brake disengages.

If you have access to another similar drive you should be able to compare things sound and feeling that’s pretty much all you can do without opening it. Which you really don’t want to do as any dust can crash the drive.

While many people today haven’t played with a phonograph playing records the HDD is just a variation of this. Here the record is the platter and if the needle runs across the record because someone bumped the player the record can be damaged. Just like a record little can be done to fix that.

if the head brake is locking on you you might try banging the drive onto a flat surface flat side down evenly to loosen it up, if the drive is being accessed and then failing the platter is likely damaged as such what ever is on the drive will be much harder to recover and some files could be badly damaged.

While expensive some drive recover houses have the needed clean room to open the drive and even replace a damaged head unit. I hope you can get your stuff recovered.