How much in common with 94/95 E320s?

[Big Yin]

The junkyard 1995 E320 wagon that I bought with pretty low expectations as a "fun" summer project has turned out to be an astonishing vehicle. Pretty nervous about setting off on a 2,000 mile road trip after replacing the cylinder head, but it performed like a trouper. And it got even better, after I figured out how to install the seal on the chain cover correctly. (Could I be single handedly responsible for the fall in world oil prices?)

I must admit to looking at the swank interiors of various 1995-ish S320s with lust, so I'm turning to the collective wisdom of the forum for guidance on a couple of possibly naive questions.

1) Is any of the interior trim (seats, door threshold, center console, dash, door liners, etc) interchangeable between my wagon and other Mercedes non-E320 bodies of the same era?

2) No heat is delivered to the driver and foot area. Any suggestions?

3) I understand S320s with the same in-line 6-cylinder came with a 5-speed transmission. Would it work as a replacement for my stock transmission?

Many thanks in advance for answers to any or all questions!