I'm 6'2" also, and I fit in my 04 with about 1" of headroom clearance. I have a 32" "inseam" so maybe that's why I fit.
Before you spend lots of cash on an aftermarket seat, make sure you've tried every position that your power seat offers.
To find a seating position just right for me, here's what I did.
While standing outside of the car, I put the seat down to it's lowest position, with the seat bottom as flat as it will go.
Put the seats "back cushion" into a 90 degree angle.
Move the seat back as far as it will go until it's up tight against the "Great Wall of Mercedes".
Now sit down and start moving the seat forward, and start raising the front of the seat until your knees come in contact with the lower dash, then move the seat backwards about an inch or two.
Next, tilt the back cusion as far as it will go until it hits the wall.
I hope it works for you as well as it does for me.