Downloaded mod in career mode

Hitman65

50RPM
Jul 11, 2011
62
3
Hi. I imported a Petronus Merc formula A mod to my PCars game and picked and saved it in my garage. But when I start my formula A career it reverts back to another team. Is there a way to fix this so I can keep the Mercedes for my career mode or is it only available in quick races??? Thanks in advance.