I had the same problem, the pahelstic clip that hold the seat down were the culprit. It's impossible to get them out w/o breaking them although i have tried to remove the seat by pushing it back first.
'99 Black/Tan SVT
#291 of 2760
Tinted
Mirko Splitter
Pioneer 8400MP & 3-way 6x8's
Clear corners
Custom SVT banner
A-Pillar pod with Volt, Oil Temp & Press. gauges
B&M
Diamond Blue Fogs
White HVAC
the99svttour@yahoo.com