William,
Like JW said, there are lots of opinions on engine color. I used Jim Carter's engine paint and it was a good match to traces I found on my engine. That being said, various factories may have used slightly different shades of grey.
As far as interior color, I bought what Jim Carter sells as the correct interior color, and it was quite a bit darker than the hidden (and I'm assuming unfaded) spots on my truck. I got it lightened at a local paint shop.
If you can find spots, like behind the speaker grille, it should be the original color and you could get it matched, although that's typically expensive ($75 plus paint cost at one paint shop here in town). The interior is slightly metallic, but is a low gloss. Also, Jim Carter's steering column color was spot on to the original on my truck. They have the Juniper Green, and would sell you some, although not likely to share the formula to get it locally.
Here is a resource that might help you. It has other manufacturer codes for Juniper Green besides the old PPG and Dupont codes.
The attached pic is from TCP Global. They may be able to mix a close version of your interior color (It doesn't have to be exact - who's gonna know

) I have not contacted them about interior color.