Hi Martin, nice work on closing the gaps - you will definitely appreciate the lack of road debris in the front !
The DRB has f/glass panels which cover the sides of the front frame & then extend out & up to achieve the same thing as you have done. For the 1st few hundred kms, I ran the car without a rubber seal on the top of these lips, & even with only a 1/4" gap there, it pulled in all manner of cr*p from the road. Once the soft rubber seals went in, all was solved.
The attached pic from way back shows these panels.
I recently decided to open up the NACA ducts on the front guards, & used some advice from Hayden M for making up the under-guard duct extensions - just use some lead sheeting for the mold. My duct extensions are only some 8" long (final destination TBA), but were dead easy to set up with the lead - just finger-tip pressure required to get the final shapes, & a few taps with a block/hammer to get nice flat surfaces. Once the glass had set, the lead sheets came away easily.
Kind Regards,
Peter D.