Were there any images of a transitary event of Jupiter or Saturn as imaged by a deep probe mission I'm quite certain that there isn't any actual images of a transitory event of Jupiter or Saturn across the solar disk from say e.g.,s the Voyager probe, Pioneer 10/11 or even recent New Horizons mission? 

Another related question I have, what would the approximate transit of Jupiter look like as seen from Saturn. The distance between Saturn and Jupiter is approximately 4-5AU, and the diameter of Jupiter is one tenth that of the Sun's. Are we looking at perhaps a transit which covers 10-15% of the solar disk?

N.B. Please note I understand that to observe a transit of Jupiter we have to be superior to it in the Solar System, hence I am asking for images taken by deep Solar System probes only.
Cassini is supposed to have used its VIMS spectrometer to observe a Venus transit from Saturn in December 2012. NASA said it was a first. They were more interested in an absorption spectrum than an image.

Celestia can model such events.
Here is a video of a simulated grazing Jupiter transit from Saturn.
There are similar videos of Saturn transits from Uranus and from Neptune.

Transits are rare events because two planets must be near the intersection of their orbital planes at the same time.
A numerical integration study by John Walker found only 1413 transits of Jupiter and 201 of Saturn from outer planets in 250000 years.
A similar, smaller study could determine whether a given spacecraft could have caught a transit on its way through the interplanetary void, but I would not expect a positive result.