Head rest supports

[<tputland@charter.net>]

Hi all. 

I saw a picture recently of a couple seat frames. No padding, etc. These seats 
had the head rest support runners down the back of the frame. 

My question is this:

Do all the seats have these head rest support runners in them? Or did Nissan 
make two different seat frames?

TIA


Tim
Belleville, WI.
'70 SPL AND SRL...and now a part car FOR SALE cheap cheap..and again, until I 
find another...
                       Still clueless but always learning