The new rear upper arm plate R848018 is the latest option part for ARC R8.4 series of cars. It moves the inside hole 2mm higher and 1mm inboard compared to the original rear upper plate R808006.

The new plate makes setup easier, it changes only the rear arm length. Using a more extended rear upper arm can give more rear traction. The arm length can be adjusted by changing the insert, each gap is 1.5mm.