I'm assuming you're talking about the fuel sending unit/pump assembly? If thats the case then use one for a fuel injected v6 Monte or Buick GN. You can get them off of Ebay. Here's several links : http://cgi.ebay.com/ebaymotors/Buick-Grand-National-GNX-New-ACDelco-Fuel-Sending-Unit_W0QQitemZ130349620247QQcmdZViewItemQQptZMotors_Car_Truck_Parts_Accessories?hash=item1e59715c17
http://cgi.ebay.com/ebaymotors/84-87-GRAND-NATIONAL-FUEL-TANK-GAS-SENDING-SENDER-UNIT_W0QQitemZ370226949812QQcmdZViewItemQQptZMotors_Car_Truck_Parts_Accessories?hash=item56333eeeb4
EDIT: Here's a cheaper one: http://cgi.ebay.com/ebaymotors/87-BUICK-REGAL-GRAND-NATIONAL-Fuel-Tank-Sending-Unit_W0QQitemZ190378799025QQcmdZViewItemQQptZMotors_Car_Truck_Parts_Accessories?hash=item2c5375efb1