Front upvc door with top light

Hi,
I want to fit a new upvc door, problem is there is a strange shaped top light above the original door.
It will cost quite alot to get one made up so i was wondering if i could just cut out the wooden frame where the door frame meets the top light on both sides. By doing this i would be leaving the old wooden frame top light in and fitting the door underneath.
I am sure this will be ok, but any suggestions will be great.

Thanks