How much meat is on a fat flatfish?

amblight

I've got these 2 babies



And together they weigh 541g. How much of that do you think is meat, that I will get to eat vs. what is just gills, tail and bone?

At this food data base http://www.foodcomp.dk/v7/fcdb_details.asp?FoodId=0236 , it's says that loss/waste with plaice is 67%. So that would suggest there's only 90g meat on each of my fish? That seems like very little! They look fatter than that.

I plan to cook the whole on the grill, so I can't just cut off the meat, and weigh that. What would you say is a closer estimate?