Windscreen wipers

[gcarm]

This is from the RMS website:

A vehicle is classed as individually constructed if it has:

• A specially constructed chassis (non-production vehicle) or a manufactured replica chassis
• A widened or narrowed chassis, either in places or along the whole length of the chassis
• A production chassis which does not retain at least one of the original structural cross-members in the same place for that chassis
• A substantial change to the arrangement of the engine and driveline, such as engine moved from front to rear or to a mid-mounted position, or if the vehicle is changed from front wheel to rear wheel drive
• A monocoque construction, where the subframe structure has undergone significant structural change, such as removal and replacement of subframes with structures of a different design, or modification of the subframe rails

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It doesn't specifically mention shortening of the chassis, only widening or narrowing of the chassis.