Using just the modification system, no. The new data overwrites the old data except in older vehicle models using the older engine modification.

However, you can use the "redesign" system located in the modifications window to create a component with a different name that uses the same configuration and sliders. This is considered a fork instead of a linear progression however, so it starts over on its own "modification" variables.

Thank you for the response, I’ll have to use that route to track the progression. By the way, I’m really loving the game, and it’s very refreshing to see a developer actually stand by their game.