Pontiac 2003 Montana Owner's Manual page 20

Adjusting the Bucket Seats
There are two adjustment levers on each seat to adjust
the seat forward or rearward.
One is located below the center, in front of the bucket
seats.
1-14
Lift up either lever and slide the seat forward or
rearward.
Release the lever. Push and pull on the seat to make
sure it is locked into place.
The other lever is located
on the rear of the bucket
seat.