I believe he has the internal snap rings.
You really can't measure the run out at the caps though. There is enough play in the slip yoke that measuring on the car will be inconsistent anyway and if you are only seeing a couple tenths then my bet is that it isn't at the end of the shaft. You should be measuring near the center of the driveshaft to check for run out. Also check the run out on the rear wheels while mounted on the car. Are they balanced properly as well? Check for flat spots on the tires too.