It would be pretty handy (and surely pretty easy..?) to show when a part was fitted in the 'assembly' screen.
It's a bit of a pain to compare the part numbers, but if I can see it's been a week since I last changed it, I would know straight away how many updates there would be. Also, it will let me know how many races it's been on the car for, which would also be handy for calculating wear!
It's best to change the engine every 1 or 2 races depending on how many you have and then the rest for every race, because seeing as your a rookie money isn't a problem and it's worth getting the max out of your car