1991 B2200, gas, Auto, Hyd Lifter Clatter Problem
 

I have a 1991 B2200, carb. automatic trans, that has Hyd lifter clatter. Truck has 214,850 miles on it. When I first got it, while still under warranty, I had one clicking and they just replaced the one. Now I have another one clicking so how do I replace them. Each lifter cost approx. $14 each. Is this a major job? And what would be the approx. cost to replace all of the lifters while the engine is open? Any help would be appreciated. :)