Just joined the Forums as I have been helped by the information that I found when searching for a solution to a problem. I wanted to first thank everyone who contributes their knowledge as it is extremely valuable when you run into something that you haven't done before.
My issue was a stuck hood but only on the passenger side. After reading the posts here, there were answers, but none seem to match my particular situation. However, there was enough to get me started in arriving at my actual solution. My hood problem was on my 66' 427 with factory air. With the outside airbox mounted where it is, there is essentially no way to reach the passenger hood latch from below with your hand. The cable that extends from the drivers side latch to the passenger side latch was the issue as it was broken and not engaging the latch. After studying the way the latch operates, I found that there is a spring that holds the latch closed when the cable isn't being pulled to open the latch. So, if that spring was removed, the latch is basically free to open. The question was how to remove the spring. With the car on my lift, from underneath, looking up along the engine side of the airbox, the spring was visible. There is just enough room to get a "broom handle" or other long device (I used a piece if 1/2" emt pipe I had in the garage) up to the spring and push it hard enough to pop it out of the hole it is mounted in. Even if I broke the spring, it is a less than $5.00 part, so I wasn't concerned about possibly breaking it. After 2 or 3 tries, I popped the spring off its mounting spot, crossed my finger and lowered the car. I grabbed the drivers side of the hood and when I tried to raise it, the hood open and I was able to see the broken cable. Upon inspection of the passenger side latch spring, no damage other than a slight bend in the original open curve that hooks in the latch spring support hole. Hooked it back in the hole and the latch functioned as normal. Ordered the replacement cable and supporting hardware and everything is back to normal. So for those who have a car with factory air and a stuck hood on the passenger side, try to pop the spring latch loose and your hood has a good chance of opening up.