GH3 or GH4- 4:3 output on external monitor for stills

[John Packard]

Is there a way to shoot stills in 4:3 using an external monitor on either the Lumix GH3 or GH4?  This would be nice in a studio or locked down high volume stills shooting situation.  My GH3s only seem to output to 16:9 on my 22" monitor.  Is the GH4 the same?