Depending on the 5th. gear ratio of the T-5, a 3.50 rear axle might be a bit too tall. Something in the 3.70 to 4.0 range might be better. If those engines might have been built in Canada, the serial number charts available for ones made south of the border won't be of much help. Try looking for casting numbers, located down near the oil pan rail just behind the timing cover. A 216 engine that I'm working on currently has the same number as the one behind the distributor stamped into the gasket surface where the pushrod cover fits, near the front of the engine.
Jerry