If I hold down Option+Cmd+P+R then I can boot into the OS on the SSD after the install and complete the setup process.
Subsequent reboots bring up the crossed out circle. I can see from the System Report for SATA/SATA Express that all three partitions had been created by the installer, EFI, Macintosh HD and Recovery HD.
I've tried the repair permissions, verify and repair disk in disk utility, nothing seems to help.
I ran the Software update, but they were only for iTunes, etc, nothing system related.
I'm reluctant to open it again and swap the drives back, I'll try the boot from original drive connected via a USB-to-SATA cable I have.