From Team Losi Racing:
We have released a new chassis for the TLR 8ight-X. The part number is TLR341022. The chassis is 3mm shorter and also moves the weight forward by moving items on the chassis forward. This chassis provides more overall grip, more corner speed, and more steering for an overall faster vehicle. We recommend this for all surfaces and in all conditions.
It is easily distinguishable as it is marked with -3mm inidcator.
You will need to modify one of two parts on your vehicle for fitment. You either need to slightly modify your center brace/servo mount or your upper battery box lid. You will see where these two touch and just want to clearance them until they do not.