I've been an Associated boy up to 2 weeks ago and decided to shift towards a new family

.
But since I'm unaware of the Losi 2WD generation and how the parts fit from an older car to a newer one, hence my question.
Does the LOSA2943 XXX Gear cover fit the newer XXX-CR ?
What parts actually can be recovered from either an XXX or BK2 and can be used on a XXX-CR ?
Thanks in advance for the help guys & girls,
Erik ( Stical )