Is it possible to put my PC-HD in my Amiga, without having to format it so I can copy some files over from my Amiga?

It depends on the type of hard drive and the file system used. If it's MSDOS or Win 3, you can transfer it to the Amiga provided it has the same sort of interface. Using CrossDOS, which comes with OS2.1+, you have to include the letter C or D as the last character in the drive name in the mountlist or DOSDriver. Here's one for an MSDOS Zip disk (a DOSDriver file called DHC). You should be able to adapt it for your needs.

CrossDOS file system entry for drive DHC:

Device = scsi.device

Unit = 6

Flags = 0

Surfaces = 1

BlocksPerTrack = 68

Reserved = 0

Interleave = 0

SecOrg = 1

LowCyl = 0 ; HighCyl = 2891

FileSystem = L:CrossDOSFileSystem

Stacksize = 4000

Priority = 5

GlobVec = -1

DosType = 0x4D534800

Buffers = 5

BufMemType = 1

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