Is the old drive still intact; all the working OS present? Is the external hard drive partitioned, or just one big partition? What filesystem is used on the external drive? How full is it currently?
Yes. Old drive is intact and PCLOS is fully functional. 1.5TB external hd is divided about in half. One partition is htsf and the other is ext4. Currently, there is about 293 GB available on the ext4 part. I can delete some old backups and regain 200+ GB more.
What I would propose is an entirely different approach, transferring the contents of the two Linux partitions to two separate directories on the ext4 partition of the external drive. To do this, you would need to reinstall the old drive into the laptop, then do the copying using the
rsync -av command as
root, from a
liveCD. When done, you would then remove the old drive, install the new one again, and reverse the process, copying the data from the two directories to the partitions on the new drive, again using the rsync -av command, as root, from a liveCD.
I use this method to move/copy operating systems on a regular basis. The OS I am typing this from, has been moved three times since it's original installation, so has resided on four different partitions on two separate hard drives. Currently there are two working copies of the same OS on two drives, and I can boot into either.
If your main concern is getting the job done, rather than the method used, I can walk you through the entire process, step by step. Seriously, I've done this literally hundreds of times, and never had a failure, to date. This is also the method by which we upgrade the main PCLinuxOS repo.