Difficulty re-attaching the oil fill tube to new coolant tank
 

I replaced my coolant tank and have gotten all of the coolant lines re-connected on the back side of the firewall.

BUT I am having a very difficult time getting the oil fill tube re-connected to the manifold on the engine-bay side of the tank. I literally spent an hour trying to wiggle it onto the manifold port including using some WD-40 to help it slip on, but I just can't get it to seat more than a few MM. The spring clamp is being held wide open w/ spring clamp pliers and I've triple checked to make sure it's not interfering.

I searched a bit and found others with similar problems, but does anyone have any tips/advice on how to get the tube to fully seat?

I was thinking about warming up the tube a bit (hot water maybe?) to see if that helps, but open to other ideas.

TIA

Liquid dish soap

It's been a while since I have replaced my tank and oil tube. I fought those stinking spring clamps, but I don't remember fighting the tube itself. Here's a few suggestions.

The oil tube has the upper accordion section that you are fighting. That attaches to the tank at one end and the other oil tube attached to the engine. Have you tried disconnecting it from the other oil tube to give you some freedom of movement?

How old is you tube? Could it be brittle/stiff and doesn't want to slide over new tank barb. My old tube had cracks in the accordion section, so I replaced it.

Heat isn't a bad option. Maybe a little dish soap with heat?

I just did this last week, like Lowski my fight was with the spring clip. I as able to get the tube on with the manifold bolted down, working from the engine side by feel only.
You might try unbolting the manifold and pulling into the trunk enough that you can see if there is something in the way. Perhaps the edge of the tube is bent over?. Heat is also an alternative... that was the only way I was able to get the rubber intake tube onto the throttle body when I swapped my engine.

For posterity - I used a heat gun on low for <1 minute to heat up the tube on the engine bay side and it slipped right on. Thanks for the tips, everyone!