actually I bought the cylinders at a swap meet for a dollar each, at the time I didn't know what length I needed so I both 2 sets of differing lengths. I will measure it and see if there is a name. These are simple truck topper hydraulic cylinders, can be purchased at any number of places. We happen to have a truck and trailer accessories place nearby so that is where I went to get the ball stud to put into the trunk hinge and trunk floor bracket that I made. Mine are welded in as this is a pretty big overall change (notice the antenna on the right rear quarter). You could do the same by bolting the bracket down (Id recommend a support plate underneath).
I like the concept that started this thread, however I wonder what level pain it would be to remove them once the car is fully assembled should a cylinder go bad. depending on the price, maybe I will try this one out on my Challenger.