ChicagoKelly,
There is a latch at the base of the back of the back seats that you will need to release to get them to flip forward. The easiest way to see/do this is to open the rear door so you can easily access everything. If you look at where the back of the seats meet the bottom of the seats you will see where the seat belts mount to the floor and pass through a hole between the backs of the seats. To get the seat flipped forward you will need to pull the seat belts through this hole first so that they are laying on the floor. Just to the right (passenger side) of where the seat belts mount to the floor you sill see a latch holding the rear seat down. Pull that level up (mine has a little strap attached to it) and then lift the seats up and flip them forward.
I have a 2000, but I think that it's the same on the 99's; there is a strap with a metal hook attached to the back of the passenger side rear seat. Once you flip the back seat forward the metal hook latches on to a metal "ring" on the floor right behing the center console (it's hidden by a flap of carpet). That will help secure the rear seats in place when they are flipped up.
Hope that helps.
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