Vintage Campagnolo bottom bracket dust shell

[jamesbowers]

Hi. I am installing vintage Campagnolo BB on my bike. Noticing the rubber dust shell of the bb consists of two parts, the longer part and the shorter part.
I am confused about which direction should the shorter part face to. The non drive side? or the drive side?
Thank you in advance for guiding me.

 

[100bikes]

Short piece on non-drive side.

The shell parts nest into the cups.
When you install the adjustable cup, the short section inserts
into the long section.

Simple and clean.

 

[juvela]

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