(Were you at McElroy's by chance?? I can't remember. )
Glad you liked the crab!
Anyhow, Yeah, when it's served in a restaurant, already cooked, just eat every bit of it. (They're VERY rich, and juicy, so be careful.)
As for how to prepare them, here's some advice I found at:
"If your fishmonger will clean the crabs for you, go for it. Otherwise, clean the crab by pulling back the top shell from the point to the center of the crab and removing the gills (the brownish fibrous layer that rests on top of the inner shell). If the top shell has an air sack in the point, gently break it with a finger. Pull off the eyes and mouth. Turn crab over and pull off the apron and intestinal vein, which is in the center of the crab bottom. Set aside."
I don't go crabbing, and when I do see crab available for purchase, it's way too expensive to bother with, so I don't have any first hand experience that's less than 5 years old, so I'm reluctant to inflict my memories on you where cleaning is concerned. So far as I remember, the advice above sounds right, and you wind up with a crab body/legs that's devoid of yuckiness.
(You're not supposed to keep females with roe, but sometimes it happens, what you do in that case is a mystery to me.)
A fruit is a vegetable with looks and money.
Plus, if you let fruit rot, it turns into wine,
something Brussels sprouts never do.
P. J. O'Rourke, humorist