The later 930 flare has a large cut out for the torsion bar- this was on the G50 1989 models. The opening is a semi circular cut that is covered by a separate panel. For the most part, you don't see this on a stock late 930 as it is covered by the outer rocker panel and the shark fin protector sticker.
When installing these on an earlier project ("RSR" etc), you end up leaving this semi circle exposed; it just does not look right to my period correct eyesight
Other than that , the flare dimensions, shape are identical from 1975 thru 1989.
The 965 turbo flares have an even larger cut out for its suspension set up- basically unusable for the amount of work it would take to complete the flare