Fuel Regulator Blueprints

[Fuel Regulator Blueprints] is a quest item only lootable by players on the quest. It is also provided for the quest.

Source
The [Fuel Regulator Blueprints] are locked in Cozzle's Footlocker at the Venture Company base of operations for Stranglethorn Vale in the north-eastern corner of the zone, in an area called Lake Nazferiti. To get the blueprints, players must first find the key to the box they are held in. The key is in the possession of Foreman Cozzle, who is located in the cabin at the top of the oil tower, coordinates (42,18). The box with the blueprints in it is located in the small house near the base of the tower. Rogues can pick the lock to the box without having to get the key.