Nice work on the Car immortalx and the Moi/blender workflow is a really good way to tackle car modelling. Thanks for sharing your technique.

One technique you might want to try in the future is output your Moi model to a dense mesh and retopo in blender with shrinkwrap modifier.
The shrinkwrap modifier would go below a 2 level subd modifier. CG Masters use this technique on their car models however they use blender to create the guide mesh instead of MoI.
https://cgmasters.com/3d-cars-inside-and-out-in-blender/