I’ve had both a single and double seat installed in my van - when I was deciding which I was going to keep (the double was tight and interfered with the kitchen - I concluded it was not really appropriate for a full camper).  

The only difference during installation was the number of cover sections removed before the seat was slid onto the rails.

> On 26-Mar-2016, at 00:54, dofunk <dofunk@YAHOO.COM> wrote:
> 
> The single seat rail covers are different from the double seat setup.
> 
> 
> 
> Sent from my Verizon Wireless 4G LTE smartphone
> -------- Original message --------
> From: Roy Nicholl <RNicholl@NBNET.NB.CA>
> Date: 03/25/2016 9:53 PM (GMT-05:00)
> To: vanagon@GERRY.VANAGON.COM
> Subject: Re: covers for extra seat rails in westy
> 
> Rails were apparently more abundant in Canada.  I’ve seen them on many 86 - 90/91 models.
> 
> The Hyena is in storage at the moment, otherwise I’d get you a set of measurements.
> 
> > On 25-Mar-2016, at 02:26, JordanVw@AOL.COM wrote:
> > 
> > in the US they were only found on '84 Wolfs ed. westys and '85 westys, and
> > some '86 westys.  that's it..
> > 
> > 
> > In a message dated 3/24/2016 9:25:33 P.M. Eastern Daylight Time,
> > greenvanagon@GMAIL.COM writes:
> > 
> > Anyone  have a pair?