Power Distibution Center and Breakers

[The_Breeze]

I was wondering if anyone here has any pics or links to such that show the inards of a PDC's panel and breakers on the 120 side.

I'm getting ready to crack it open to do some wiring and looking some foresight into physical characteristics/what to expect. I am full time and have to limit down time, specifically for the fridge. I was also gong to disable 12v circuits just to be safe (aka absolutely no power). I'll trip the 50A breaker at the battery box to achieve that disconnect.

I'd expect the PDC to look like and sticks and bricks breaker panel and that would probably be my first mistake. Well, not my first but the next of many.

Thanks in advance for any help you offer.