Is there no other way apart from disconnecting my both internal HDD's?

So eventually I unplugged my internal HDD's and installed BT4 on to my USB HDD. I did everything exactly like the last time...

I just wanted to write this post to hopefuly solve my problem and also express my huge dissapointment in attempt to install BT4 (following the official tutorial). My machine is HP Pavillion dv8 x64...