Rear seats back IN?

I have a 1996 auto model. I bought it from a previous owner who had all the seats taken out. Ive managed to get 3 extra seats right behind the driver in (1 single seat plus 2 swirl seats next to eachother). But now id like to include the 3 seater at the back in. 
I cant manage to feed the seat stand with Little wheels (with the little plug that helps the whole lot slide back and forward) in beyond the first feed. 
Ive taken the bolts that is in the way before the entrance of the railings out and moved the carpet to get more space, but it wont do it. 
Am i missing something? Is there any info online on this? 
I hope this makes sense?

I once saw an Australian girl do that in a video, it's not as straightforward as it looks for some reason that escapes me.
The video must still be around so have a search, you may have to take the runners off (with cables) to do it.

I found this guide online that details exactly how to remove the rear seat so that may suggest clues for putting it back.

http://toyota-granvia.co.uk/viewtopic.php?f=7&t=27

HTH