Seat trim?

Hey all. New here. Thanks for warm welcome. I am finishing a Road King trike kit and upon re-installing seat there is a noticeable gap around the passenger seat that does not look good. I checked with manufacturer and was told it's correct kit etc. No help. Do you thing a Mustang wide seat or something similar would work? Thanks!

welcome Patrick

I'm guessing a big wide seat would be the answer. They are expensive but maybe a used Harley Road Zeppelin would be the answer. A very comfortable seat and it is bigger then the normal seats. I've been riding on one for 15 years.