Xīn lóng International Airport - Airbridges

You can't have a modern airport without airbridges (or jetways if you prefer the term). In the past I'd made my own for my 1:600 scale endeavours however for a 1:400 airport they need to look a bit better which means buying them in. The only widely available airbridges in 1:400 are made by Gemini but can someone explain what's going on with these...

I own several sets of the Gemini jetways, which though quite simple are still pretty nice and can be easily improved with some marker and stickers at least. Gemini sell both narrowbody and widebody sets which aside from the terminal connectors, and ladder lengths, are the same. The airbridges themselves come in two lengths however I have noticed that even when used with the widebody connector the bridges sit too high off the ground for the wheels to be in contact. If you extend them further out then they are too low for a widebody aircraft. You can see what I mean in the below shots:

I am sure I have seen version of the bridges with extended wheels so that they are tall enough, but I'm buggered if I can work out how to do it. Am I just being stupid? I have tried to extend them but that just broke the airbridge, however it seems bizarre that these are sold with the widebody sets only to be too short to be used properly (especially when the ladders are long enough). Can someone explain what, if anything, I'm doing wrong?

Anyway an alternative fix I tried out was to break the wheels off and slip in a piece of plastic tube so the gates are tall enough. It looks ok but I'd rather the Gemini bridges worked properly. What do you think?