Hello with Ford E350 1999 old shuttlebus

[Q'willWorks]

Hi there everyone,
Dearest husband and I got us a shuttle bus that is note a work in progress.
Looking for information about weatherizing the interior.
First of the walls. I noticed there is some insulating Styrofoam looking material between the outer walks of the bus and the inner walls. I would like to pit some wood paneling to give it a homier look than the plastic (?) now present. So is it possible to just leave the existing walls up and put the panel up over our is it best to remove existing interior walls. Would the existing insulation be sufficient?
A bit nervous about removing then since it looks like they are riveted in and it seems like a challenge.
Same issue with the roof.
Any help would be greatly appreciated.
Check out the photos.
Thanks to all!

[Carytowncat]

Welcome, glad you are here

I skipped insulating because i wasn't sure about the bus yet, but others here have lots of experience.

[Q'willWorks]

Thanks Carytowncat. Looking forward to getting some of that knowledge. Don't wanna get overwhelmed and quit! Hoping to use the bus in the summer and winter!

[Carytowncat]

I hear ya, one day at a time.