A couple of comments on SA engines. I know the 5 cylinders are mounted
at only a 5 degree angle. I believe the 4 cylinders were too. With this
mounting you can use different engine mounts than what Tiico supplies.
And those should reduce or eliminate the vibration factor.

The Tiico kit essentially is using a diesel mounting bracket to tip the
engine over sufficiently to get under the regular deck (the SA Vanagons
have a raised deck lid).

So all of the questions regarding "how could VW SA design something
like this?" may be entirely moot. The didn't (I believe).