Botom braket removal Advice please.

[afp401]

I had a wee go at it but it's not budging.
Before I crank up the force I wanted to ask: Do I remove this like a normal cartridge Botom bracket.
It looks like one to me but then I spotted the threads and wee nut on the axle so started to wonder if i have to remove that first?
I'll give it a scrub before i try again too.
Thanks
Steph

 

[legrandefromage]

Its one of the earlier design of Shimano cartridge BB, best not undo the nut because nothing happens afterward.

viewtopic.php?f=1&t=98595&hilit=removal

*Marin or Fusion?

 

[afp401]

Re:

Thank you! Will give that a go. What thread/diameter was the forced in bolt to start with please?
Edit and yes its a marin.