Yes, Oklahoma Joes is serving soft-shell crab Po' Boys on Fridays during Lent (through April 2). They also offer a fried-filet-of-fish version of their Z Man (with Provolone and an onion ring). Both are sold as a "meal" with one side. The crab Po' Boy is $8.99 and it includes one side (get the fries).
I tried the soft-shell crab last night and it was OK; they serve it on a soft hoagie-style bun with a smear of "remoulade" sauce (think it was mayo, pickles and their bbq sauce), a blob of their creamy slaw and two tomato slices. The slaw and sauce balanced well with the flavors of the crab, but the winter tomatoes didn't bring much to the party.
I took mine to go, and by the time I got home, the bun had gotten pretty soggy. It wasn't great bread to begin with (a bit too soft and too sweet) so I ended up dismantling most of my sandwich. The crab was OK; generously breaded, not too fishy tasting, with a good crunch from the breading. It too got soggy from the slaw over time, but the flavor profiles worked fine together.