in what way is it different? I fitted the uprated arm with the grease nipple on my rover 400 when I swapped the clutch, and from memory (it was nearly 10 years ago!) I dont recall noticing any significant variations in geometry as far as arm or fork compared to original.
Sadly I dont think I took photos, but I did have them out side by side, so feel fairly sure I would have remembered a difference if there was one.
edit: yup... there is a side by side by side pic on the the (ahem!) other well known forum
http://forums.mg-rover.org/mgf-mgtf-%2Asponsored-mgfntfbitz-mgf-mg-tf-parts-01457-238202%2A-12/fitting-modified-clutch-release-arm-296767/