I backed up the main HD to an External SSD via USB and Time Machine. No problems there at all.
Sounds ok, but TM does not make a normally bootable drive. It is possible to boot from a TM drive, but to do that hold CMD+R down at boot and wait for the TM drive to show up as a boot source. Bear in mind that if that is the internal SSD, then you won't be able to install to that drive as that is where you have booted from. So if the SSD with the TM backup is external and you boot from it, then you can use Disk utility to format the internal drive and I think you can then restore from TM to that drive and should end up with the new internal being bootable.
I also tried formatting the new SSD via USB with MAC OS Journaled (extended). Then I put that SSD in the main Bay, then tried to boot with option key and I get the blank screen with mouse pointer.
Yep, formatting does NOT install anything, just formats the drive to be empty, so the drive is blank, leading to the blank screen. So basically what you got is what you should have, i.e., nothing.
A different thread suggested that I may need an upgraded SATA cable for the newer SSD? Can anyone confirm that?
Not at this point. So far you have been able to work with the internals (see, format, etc) so the cable is functioning. It is always possible for the cable to go bad, particularly if you are working with it a lot, but at this point I see no reason to suspect it. You don't need a new one just because of the SSDs, if that was what you meant. The same cable should work with both the old HD and the new SSDs.
Sounds like I may not have the right recovery partition on the new SSDs?
At this point, you have nothing on the new SSDs, since you formatted them, if I understand what you have said. And when you made the TM backups to them, that didn't create any recovery partition, either, so it's not that you don't have the right partition, it's that you have no recovery partition as you have not installed any OS to them.
Oh, one more thing. When I have the SSD connected via USB externally, using the option key does work and I can select device to boot from. If I select the external SSD, I'm directed down the path to begin reinstall and starts asking me to choose language, etc. Looks like I just need a good internet access and then I can install new OS X.
That result implies that there is something on the SSD so that is a good thing, sort of.
I can try to clone the HD to the new SSD...but will wait for more feedback.
Thanks for all your input!
I think what is happening when you use the Option key you are getting to an Internet restore somehow. You can read these for information:
https://support.apple.com/en-us/HT201314 https://support.apple.com/en-us/HT204904
Cloning the HD will just clone the TM backup, which is not normally bootable. What I would try is to put the SSD internal, then boot using CMD+R from the external HD with TM on it, run Disk Utility from there to clean erase the internal SSD, then use TM from the External to restore to the Internal SSD.
https://support.apple.com/en-us/HT203981 should help. Good luck with it. Keep the TM backup for a while, it may be handy to have just in case the install doesn't work properly.