old burton boots don't fit new burton bindings.

I have some old Burton Freestyle boots (circa 98-99; white) size 12 and
they are BIG and have always been bigger that just about any other boot
i've seen. Problem is, I got some new bindings recently and no matter
how I set my board I can't get my boots even close to fitting. The
bindings are Burton 2005 Mission that have the semi-new toe-grabbing
end (my old bindings were regular top-of-boot). Is it possible the
boots just aren't meant to fit? Do I have to buy new boots just
because I got new bindings?

I tried taking the liner out, no deal. Also even with the bindings set
as far back as possible my toe is pretty far over the edge.

Thanks