If I were you, would do the following way:
First install new OS on the primary HDD (master), put deleted HDD as slave. Your PC recognized it as unpartitioned, so use
partition recovery software. Just right click on unpartition area, and chose "recover partition". Other work will be done automatically.
But if you want to recover both HDDs, you'd better use third HDD or another PC:
1. install new OS on another HDD (master), put deleted HDDs as slave. Your PC recognized them as unpartitioned, so use partition recovery software. Right click on unpartition area, and chose "recover partition". Other work will be done automatically.
2. install on another PS Disk Director, use bootable media builder> create bootable CD> insert in your PC and during boot, it'll start up partition managemant window, where you could choose recovery tool.
I recommend you to try one of these ways, as it really helped me many times, this software could restore even corrupt and lost partition. Also it has friendly and very convenient intuitive wizard, so you couldn't make any changes by accident.