LDV Deliver 9 Van Roof Extension

I am looking for an experienced automotive engineer, with a specialization in mechanical systems, to assist with a van modification project. Specifically, I need help with a roof extension for my LDV Deliver 9 van, designed to increase our cargo space. Familiarity with LDV models and their specific requirements, as well as knowledge about vehicle registration compliance is necessary. Proper functioning and aesthetics of the extension are of utmost importance to me, as is its legality. An understanding of complex electrical and fuel systems is not critical, but could be a beneficial plus.