It's not been easy. There are a lot of changes. Many of the pages on my original sheet will need to be entirely changed. A problem that I always face is deciding which calculations should be automatic and which should be inputted by the players. The other major problem is organizing the information in such a way that the players can find what they are looking for without too much trouble. In this system, I think that will mean that my pages will be divided up in the same way the book divides up the character creation process, but I'm not certain.
The 3.5 and 3.6 sheets took me an entire spring break of at least eight hour days to put together, plus months (years) of tweaking since then. I suppose I should expect something similar for the 5e sheet as well. Oddly, I look forward to the challenge.