Broken piston Skirt?

[Dan]

Okay, I have an '02 Roush GT with 42K miles that was bought about a year/6,000 miles ago and have had no problems, excessive oil use or "funny" noises. I'm not the original owner. I went to a local speed shop that works mostly on Ford modular motors. The shop was to install a set of 3.73 gears, a new lower intake, upper plenum and throttle body. The owner of the shop said the rear end had been opened up before and there was excessive wear on the bearings, indicating hard starts. The intake mods went well but when we started it up there was a major, regular ticking sound, almost like a knock but not that deep of a tone. The noise sounded like it was coming from the driver's side front piston. The mechanic thought it could be one of the tensioners for the cam chain was bad or there was a piston with a broken or cracked piston skirt. A compression check was within specs. We removed the front cover and everything looked normal but replaced the tensioner on the driver's side anyway. We remove the intake, and looked into the heads. Everything looked completely normal. We buttoned everything up and started it again. It ran for a while, the tapping stopped briefly but started again. Now he wants to pull the oil pan and see what he finds but is pretty convinced I'll need to rebuild the short block. I have no doubt as to the integrity of this shop, they have a good reputation. Has anyone had any experience in this area?