Hi j.,
I have not yet tried to "convert" one of my BOLs into an E500, but according to the spare parts listings at the (reputable) dealers, the only parts NOTidentical between the two are:
* Fuselage (
http://www.helidirect.com/esky-fusel...00-p-19732.hdx ),
* Battery Holder (
http://www.helidirect.com/esky-batte...00-p-19766.hdx )
and
* landing skid (
http://www.helidirect.com/esky-landi...00-p-19770.hdx ) ...
Everything else looks to be 100% identical (but I can only say that for sure once I get those 3 parts and do a conversion .... and this might be a little while ...

Sven