part number help

[fozzyskye]

hi i have a spare set of front lower arms part numbers 8n0407157 and 8n0407158 am wondering if they are the same as 8n0407165 0nes cant find any info on them also gonna polly bush them is it best to do both or just the frontand what size powerflex bushes i will need any help would be great guys

 

[superkarl]

If they're cast arms you can use them on your S3.
Measure the arms and voila, that's what size bushes you need.