I have an '88 Pontiac Firebird formula, which is putting a new 3.50 engine in. I cannot tell if it's an orifice tube or not and where it's located.
If it’s an ’88, it will have an orifice tube. They have always had orifice tubes. Most of the orifice tubes on GM products come off of the condenser in the front of a vehicle. The hose that comes out of the condenser and goes out towards the firewall where the AC evaporator is has a little lump in it, usually close to the condenser. The orifice tube is usually hidden inside. If you really want to get picture of the stuff, have a mechanic take a look at the car to see if they can help you access it.