I took my wife's 850 appart to change out the light bulbs...It was a while ago so I don't remember all the "Tricks" but it wasn't really that hard. I recall the screws were T-15 and T-20 heads so be sure to attack it with the right bits. I would suggest taking about 3 hours and setting it aside, carefully remove a section at a time and work in as far as you want to go. Nothing needed to be forced so if it isn't coming out, look for the fasteners... I hope that this is of some worth to you. Good Luck!