My struts are replaced by Fiat Tipo gasstruts.
They have to be very warned out, because from new they are 270N force, and that is to much for glas (needs 210N), it will break if tension is to high.
Control it on a weight scale.
They are a bit short, so I put 4cm M6 bushes on it.
Because I have a Ferarri Tail the power doesn't matter much, so I put new ones on.
Don't keep youre head above it, it's a knock out
The plastic fits ok, and the the other end you can screw it in the old plastic.
If you don't like the brons bushes you can paint them or put some cable shrink plastic on them.
Here a experiment with 2 bushes.
8 cm was to much.
I don't know how the windowheater is sorted out in a Tipo, but for me it was not important.
New struts were €20+€10 shipping on E-bay.