and for the detail enhancements I added, here’s the complete list based on the NASA EVA checklists and reference photos I managed to get online:
1. I discovered that both truss have 2 pairs of additional internal support beams, the first pair is found bolted on the inboard truss wall (where they are bolted onto the S-0 truss) on one end, and their other ends bolted onto one of the interior beams that supports the Ammonia Tank Assembly...
the second pair is found bolted on one end to the truss bulkhead where the Flex Hose Rotary Adapter / Thermal Radiator Rotary Joint is mounted, and their other end bolted onto yet another interior truss beam, almost adjacent to the truss long beams
I used appropriately-sized plastic rod (painted flat aluminum) to simulate the support beams, although you can use a rolled up piece of paper as a direct subsitute
2. I used some metal wire to simulate the metallic hosings for the Pump Module. then after closing the truss up, I glued a rectangular piece of quilted paper to cover it up, simulating the thermal cloth cover that I found via flyaround photos
take note however that this detail piece can be omitted because once the truss is finished up, its almost completely hidden from view, but I chose to put them on anyway because, why not
3. like the S-0 truss, I used EZ line to simulate the wiring and cabling on the interior, as well as flexible black plastic rods to simulate additional hosing on the FHRC truss bulkhead
4. this is perhaps the most challenging detail piece I had to make (but not too hard) - there is a thin metal wiring rack that is mounted right beside the DDCU box on the outboard side of the truss... basing on photos, I scratchbuilt one using one of the unused prints of a truss bulkhead as reference, then slapped on some flat aluminum paint, then used EZ line for the wiring, then glued it on the required spot
5. if you noticed, there’s a printout of a truss-like pattern on the interior skin of the truss... its because the box-like wiring racks on the exterior of the truss is open on the inside... so to simulate it, I just used a copy of the wiring rack from the S-0 truss as a template, then copy/paste a bunch to form a strip of that pattern, print it to the required length and width, and glued them on the interior skin, directly where the wire rack boxes sit on the outside... then, like what I did with S-0, glued a second set of truss beams to give them a 3D look
6. for the radiator support racks, I decided to cut the lattice structure open for a better look, as well as open the dark portions on the radiator joint panels themselves... also, I added the grapple bar supports that were placed by the STS-131 spacewalkers...
also, you will notice that the hoses on the radiator beams are now 3D... I used plastic rods again for this to save time
7. the CETA carts and FHRCs received some minor improvements by way of plastic rods (colored gold) for the CETA Cart handles, colored wire for the handrails, and extra bits of detail pieces (extracted from spare printouts) to give them a bit more 3D look onto them
8. I made a simple paper cover on the outboard side of the Ammonia Tank Assembly to simulate the thermal cover for the hoses