MGameros:
I tried looking for a picture of one via the internet and couldnt' find one.
I think you could do it, since George has gone through a different route according to these pictures...
https://sprinter-source.com/forums/showthread.php?t=730&highlight=seats
...you can see cutouts in the wooden floor for the seat receptacles. I'm not sure if the metal base is stamped for the receptacles, but it does look like they are in Georges pictures. Even if the metal base is not stamped for the receptacles, you might be able to do it with the wooden floor acting as a spacer so that the receptacles mount flush through the floor to the metal base.
It's interesting to see that George has a 140, and there is a third rectangular hole cutout in the wood for the 2 seater position.
And it looks like the metal is also stamped in that location.
I'll have to crawl underneath my vehicle to see if there's stampings. If not, I believe you can do it.
Seek