How to install a dipstick tube without ruining it in a 440
You could try what he ^ said.
Then put the tube in the freezer over night. Put some lube on it and it might slide right in.
I recall seeing an installer tool that was basically a tube large enough to go over the tube but with 1/4 of a side removed. Like a fitting wrench.
It fits on the step in the new tube and you tap on it to tap the tube in.
Like this