I've just had the front end of my bus replaced as the window aperture all around was non existent - the windscreen was held in place by the previous owners filler

Now I have bought the flatter windscreen seal and chrome seal from VW Emporium...(the same as on the wiki - footwell leaks article)
...One question, how on earth do I fit the chrome infill without ruining the windscreen rubber.
I've used a tiny amount of washing up liquid to lube the rubber and chrome but the gap in the rubber where the chrome sits in is so tight it's only just possible to get a flat head screwdriver in it. I don't want to tear the rubber so I can't prize the rubber gap open for fear of tearing it.
I had managed to get about 2mm of the chrome strip to sit in the rubber correctly, but then I'm faced with how to get the rest of the rubber over the lips of the chrome all around the aperture.
It's driving me mad. I refuse to be beaten by a pesky bit of rubber and chrome plastic

As always, any advice greatly appreciated -