SX3 chassis query

[afun1979]

I need some help regarding the SX3 chassis.
I'm just in the process of making some SX3 chassis protectors and i've noticed that the chassis i've got hold of is slightly different to the one's schumacher sell which are also different to the one pictured on their advert car - and even that has 2 different chassis' - with and without motor cut-out...?
http://www.racing-cars.com/pp/Car_Showroom/CAT_SX3.html

Some chassis' have 2 cut-outs for the spur and some have different length motor and motor clamp cut-outs - is there a "latest" version and if so which one?

Here is "my" version, it's a S1 chassis covered in my Carbon fibre effect chassis cover but i'm just unsure which cut outs are needed or not?
Thanks in advance.
Andy.