Large Scale Central

PIKO Wood Combine - Remove Roof

I am attempting to disassemble a PIKO 38622 Blue Comet Wood Combine for painting and modification into a roadside dinner.
 
In the spirit of the Hippocratic Oath to "do no harm", I cannot figure out how to remove the roof to gain access to the interior.  I can see two screws but no reasonable way, short of drilling holes in the floor (which I also cannot remove).  
 
Any hints or guidance will greatly be appreciated.   Thanks.

Watch

https://www.youtube.com/watch?time_continue=129&v=G0xqH34R58g

About 2 minutes in.

Dan:

You “Da Man”!!! Thank you so very much.

Even with the video, it’s still a heck of a struggle. It would have been easier if I had three hands and arms like Popeye! But it’s now off with nothing broken. Now the real fun begins with cutting and painting.