I would definately do a complete inspection of every fuel line & fitting from front to back, including taking the air cleaner off and check all lines, joints & unions on the carbs. If you find an old, hard cracked fuel hose resign yourself to replacing them all.
Welcome to the club, I also have LM 002 1988 with gas odor. This is common to all LM remember the entire back seat is a gas tank. The smell is endemic to the pores in the welds. Solution is to encapsulate the tank. I have heard that some fiberglass the tank. It's not as bad when the tank is less full.
Does your LM have the flexible fuel line running inside next to the rocker like on the Espada. If so, do replace it with a solid line. This fix is on the old Lambo site under V12 tips -Espada gas smell.
Maybe you guys can help me I have somewhat of a differn't smell from my honda..... when i roll down the windows while driving, it smells like ammonia. I am guessing its a dead mouse or something... anyone ever had this happen?
I have a true story.
I work for a new car dealer. About once a year, we get customer or two that comes in with a bad smell and a noisey blower motor. When we take the evap. box apart we find a dead mouse in the "squirrel" cage. We are required to save the defective parts, so we bag up the mouse and show it to the customer. You should see some of the looks and responses. lol