How to Modify Early Inner Seat Rails for Late Car?

[Lengrep]

Early style inner seat rails are still available from BMW (for a price).  I've been told it's an easy modification to adapt them to a late (1974) car.  What's involved?

[jgerock]

Early seat mounts have a tab at the front where the bolt attaches horizontally to the body. Later mounts don't have the tab.  The sliders are completely different between early and later cars.

[Lengrep]

23 minutes ago, jgerock said:

Early seat mounts have a tab at the front where the bolt attaches horizontally to the body. Later mounts don't have the tab.  The sliders are completely different between early and later cars.

 

Okay; glad I asked!!