[Jaguartvr]

You will never be able to fit a new carpet that looks as good as the original so I would strongly suggest you keep it. A good shampoo and hoover is a good idea at this point.
I'm on the fence on the interior upgrades, I drove my car over to my painter (finally) and had the door cards removed, there is no way I could live with a car that didn't have arm rests on the doors. I even made up a "Henley's" centre arm rest for my MK2 Jag as I found it so uncomfortable to drive without the centre armrest, it was a period accessory at the time.
I do however like the retro dash and dials but would it work with the more modern interior?
I have bought a pair of MGB seats that I intend to fix to the existing seat bases. I will probably fit them with the worn and many covers to see how I get on with them, if they are uncomfortable I will just remove them and refit the originals.
And finally, sacrilege I know, but I would really like to fit a hidden pop up sat nav system in the centre of the retro dash, just behind where the fresh air vents would have been. I use mine all the time as I always have the safety camera feature turned on, as I do like to drive safely!
I have found that it is the cameras that you go past on a regular basis are the buggers that normally catch you out.

Tynoprime was doing a great job on his interior upgrades on his MX5 kit. He has been a bit quiet but hopefully now the weather is improving he might start up again.