Ok I will say again if you put the two panels in series they need to be absolutely identical. Even one burned out led will toast both panels.
BUT. YOu can get a DC/DC converter This works rather well around 90% or efficient.. and converts 12 volts to anywhere between a volt or 2 and around 10. (Some are adjustable) Allelectronics.com has some usually on sale (right now it's a UP-Verter that's on sale not a down)
YOu see magic happen when you use one of these. By Magic I mean if the LED's are powerful enough they might draw say 2 amps.. And the DC/DC converter will be putting out 2 amps. but the INPUT will only be one.
It not only converted 12 volts to six. but ``1 amp to 2 (Watts remain the same though `12/12)
