From the source machine in Windows

1. Click Start > Administrative Tools > Server Manager
2. Go to Storage > Disk Management
   This will give you the minimum size required for each partition
   
3. Right click on the disk and select “Properties”
   
4. Go to the “Volumes” tab
   This will give you the overall disk size and tell you if it’s MBR or GPT
   

From the ShadowProtect recovery environment

1. Open Shadow Protect
2. Click “Explore Backup Image”
   
3. Browse to and select a backup image you want
4. Type in the encryption password
   
5. Expand “Image File Properties”
   This value will give you the original size of the volume
   
6. Scroll down and expand “Original Partition Information”
   The value of “Style” will tell you if the disk is GPT or MBR