Everybody makes mistakes. some of us many times... If you look about halfway down this page you can see the two parts to the pontiac dipstick tube.http://www3.telus.net/68bird/engine_bottom_end.htm the top half of the tube could be installed from the outside of the block but the bottom half goes on before the pan and there would be no way to do it from the outside. with the top half in you could insert the dipstick but it would not be directed into the correct area of the pan and may contact the rotating crankshaft... I guess a person could fill the crankcase with the correct amount of oil, then insert a dipstick and mark where it goes to . then remove the dipstick and somehow seal the tube without the dipstick for while the engine is running? then just remove the cap and insert the dipstick for when you want to check the oil level? maybe?
