Hi Julius, thanks for the questions.
Small teams that communicate with each other when they are stuck is probably the most efficient way to go, so assuming we get the number of people who are signed up for this project, we probably should split up a bit. (also even for I large team, wrapping fortran code to work here may be a multi-day project and not the best use of time for those most interested in exploring the science)
I am thinking we will wrap some adapted portion of layers_fluxcalc.F in the MITgcm code. I will lead/co-lead a group to do this. If we have people who want to move ahead with xhistogram then they can split off and I am happy to spend time with them getting the technicalities working - that group would also be more linked to Water Masses of the Future.