Question about the waistlevel viewfinder and framing

Hi I decided to buy a Pentacon six TL (fully serviced and calibrated). Could not resist the esthetics any longer 😀

While waiting for it to arrive, I have been trying to read up on how to avoid the common issues. I then noticed that people are saying the WLF doesn't cover 100%. Is there anywhere I can see how the WLF coverage is? I mean is it that one see too much or simply not the whole image or do you need to acount for lacking part in the bottom etc? Would really like some advice before testing it. Lenses are CZJ 50mm, 80mm and 180mm if that will influnce it in any way.

I'm used to my Kowa Six, and Minolta Autocord. The latter has a parallax of course, but didn't expect that in SLRs.

Thanks in advance.

PS: Is there a danger to burn holes in the shutter with all lenses in the sun or are some more prone? Saw a video where that happened.