I statted it out using ship description from our campaign, looking through canonical descriptions, and also borrowing some stuff from Anders Sandberg's "EP Navel Strategy" guide. I used GURPS Vehicles and GURPS Transhuman Space vehicle/spacecraft-building rules. Some vital stats (these might still change if/when I shift some figures around):
Captain Garb stands at the junction of the cargo spine and engeering section. Each square is a meter. Actually, I think I mis-scaled this entire thing by a factor of two: the ship should be half as big.
Here is the entire ship. Properly scaled, that cargo spine should be a little over 25 meters long (that is, about a quarter of a football field). There are actually a total of six heat radiators, but I only drew one so far. The spin section is actually four separate pods, but I lazily just drew the entire thing as a cylinder. It spins at 2 PRM to achieve about 0.1g (a bit less than Luna).
I might continue at this for awhile: theere is plenty I could add (e.g. solar panels).
One thing to note is that, if the fusion reactors are shut down, they require an external energy source to ignite the reaction: basically a real powerful laser is shot at a point in the reactor for a nanosecond. This can be achieved via, essentially, really powerful batteries/capacitors. The batteries are then recharged from the fusion reactor (for the next time they shut down), or via another energy source (solar panels, RTG, etc).