Refitting rear torsion bars without original reference points

[giraffeinbath]

I need to refit the rear torsion bars into our '68 T2 but unfortunataly the reference marks I made on the bars and chassis have scrubbed off during the work so there's no reference to their original position. Obviously there are a million video's of folk demonstrating how they can be rotated to adjust ride height but I've found nothing providing any guidance to refitting the bars from scratch. I assume the difficuly will be matching them so they are even left to right.

If anyone could provide some guidance or point me to a useful reference it would be much appretiated.

 

[sparkywig]

Is this to reset the rear ride height?
If so, @Fortunate Son is your man having just done this on his Adventurewagen.

 

[giraffeinbath]

Is this to reset the rear ride height?
If so, @Fortunate Son is your man having just done this on his Adventurewagen.

I guess so yes. As I say, the torsion bars are out of the vehichle and the original sharpy pen ( I know.., I know... ) reference points have scrubbed off so I have no indication of their original rotation when inserted. I can't see any factory marks either so how did they know which spline the inner and outer ends were to be set to in factory during assembly?