WANT TO BUT MPI for my starion

for an 88 conquest on Saturday my best friend bought this car 2years ago and owned it till last july wheb he sold it to a gentleman in indiana and I lost track of it until a month ago when I saw a car I recognized on face book and messaged him saying who I was and told him if he ever decides to sell to call me first turns out he wants a montero ill post a picture in a few my friend named her ruby the first day he had it and she's keepin that name   BACK IN THE GAME

We checked the system and he said ...get a new valve because yours is not opening ...and get a new dryer while your down at the parts store....is there any way to make it unstick ????I have a propane tank full of r12 so i dont have to change to r134...Is it hard to get to the valve that is sticking??? to change out....????? he replaced the relay for the cluch and everything else is good..