The interior looks great. The finish on the seats might be a little to shinny for leather or vinyl, maybe just a light dusting of semi-gloss ?? Very impressive wiring for the firewall. I like the decal on the oil filter also. For the foam on the Air Filter, there are many sources of material you could use. If you receive anything at home or work that has those very thin foam wrappings is one that comes to mind. Overall it looks like you have it coming together just fine. Look forward to seeing how the rest of this build comes together.