lright guys, Here's step by step on how to remove the chassis to un-lock the exhaust cover lid.

1. Remove 6 bolts that I indicated in 'Green'
2. Pry out tires very carefully.
3. Remove 2 bolts in red area. (These two bolts holds the rear bumper in place)
4. After removing 2 bolts in red area, slowly wiggle the rear bumper loose (Bottom chassis is pretty loose at this point and you should be able to wiggle the rear bumper off)
5. You should be able to get to the single bolt that's holding the lid shut.
6. If you can't not get to the bolt this way, go ahead separate the chassis from the body. It should be very easy to do and don't be afraid ,but I doubt you have to do that.



Here's some more picture of the Exhaust lid open