It really depends on what the starting point for the car is.
If it needs a total restoration, as many do, why not do it properly ? They were never designed to last for 50+ years and some of the structural elements should be renewed as a matter of course IMHO.
If it doesn't need a restoration then don't do it. Simples.
E Types were built to a price and like many cars of the period rustproofing was virtually non-existent.
It makes sense on a full restoration to take a little more time over panel fit, paint and rustproofing etc. It will pay dividends in the long term.
