Dipstick won't go back in

famous bob said

does it have a windage tray in it? could be hanging up on it, a stud girdle, or even the pan gasket.---ask me how I know !

Click to expand...

I believe all 340 LA motors had windage trays. I did not rebuild motor, so can't say for sure if mine has one or not.
The mystery is how I can insert a plastic rod and it goes in smoothly without hanging up. Makes no sense,
and it seems this will remain a mystery.
I appreciate all the input.