It's also possible he did exactly as stated, but the cover wedged in there and upset something. Those bolts are such a PITA to tighten.. I have a handful of spare wrenches I bent, cut, and ground to help R&R manifolds and I still hate it!
i will double check the clearance of the valve covers, but i moved them back, installed the intake, then tightened it. I loosely set the valve covers back on and took them back off the next day to replace the valve cover gaskets.
