1970 Almond green Traveller Respray

[culp]

Hello, I'm just at the point of finishing the welding and starting the painting of the bodyshell of my 1970 Traveller. I'm aiming for as good a finish as I can get and as original as possible and doing it at home with cellulose. It was Almond Green

I thought I'd start with the underside.

What's a good primer to use? I'd like to get a close as possible to the original that appears to have been black.
If I clean up the weld seams with a wire brush do I need to use a rust treatment? If so what's a good one to use?
Am I right that the underside was primed, then treated with stone-chip then painted the body colour over the top?
Recommended Paint supplier?

Then the wheel arches

Same finish as the underside? or just primer then body colour?

Then the interior, the bits eventually covered by the trim and carpets

There appears to have been some sort of sound deadening at the back under the seats and inside the doors, most of it's gone with the rusty panels, any idea what it was and how I recreate it?

All advice very gratefully received

[les]

Regarding the floor covering, I have used ‘Hammerite stone chip shield‘ from an aerosol, hold the can at a distance and it duplicates the factory finish, after the car’s top coat is sprayed over it.