The lifter bodies are slightly taller than the stock ones that came from the factory in the 5.0's (the cups are seated deeper so there is no issue with pushrod length). I've seen internet reviews where some installers could not get the lifters on the far ends of the block to install with the heads on. It was a bit tight and I had to turn and angle them into the lifter bores, was able to do this with GT40P heads installed. No head removal required. Received shipment with-in a week with no issues.
