I found this info on the instructions for the retrofit kits

Retrofit kit No. 51 71 0 398 335 without running boards (door sills) no
51 71 0 398 336 with running boards (door sills) yes

Parts list (6 pieces 4.6/4.8 front and rear arch trim plus bumper flares)

A Left flared bumper
B Right flared bumper
C Left template
D Right template
E Retaining springs (14x)
F Front right wheel arch trim
G Rear right wheel arch trim
H Front left wheel arch trim
I Rear left wheel arch trim
J Blind rivet (30x)
K Expanding rivet (6x)
L Blind rivet (2x)

Maybe somebody else can confirm this

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2002 X5 4.4
White /Premium Pkg/ Cold Weather Pkg/ Sport Pkg
sand beige leather with light poplar wood trim, ACS Aluminium pedals, Running Boards, 20's oem style 87, 4.6 kit, BMW Hitch, K&N Filter

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