308 Bits at Shapeways has 1/2700 3D resin parts that many builders have used with great success. I also used Falcon 3Ds upgrade parts for the radar domes, engine bells and Hyperdrive engines and the garbage chute etc.
It is too thin. Part of the reason is due to the use of a digital model element from Rogue One on their ISD -I class, which for some reason, the retail specs have the side trenches far too thin, as much as the old MPC kit's side trenches were too tall. I ended up manually increasing the trench height by 3.2MM or 1/8" but that caused some other serious issues - specifically with the engine block and the top and bottom hull fitting. My build thread showcases what I had to do to deal with that.
I got a whole bunch of Plastruct and Evergreen styrene rods, tubes in myriad sizes and widths about 4 years ago when the prices were somewhat affordable and you could actually obtain them at model shops online. That was back when I was in furious greeblie build mode. Nowadays getting styrene is almost as difficult as finding and getting lumber and 4x8 sheets of plywood at a price that will not break you.
Currently I am at the detailing and panel line stage of the hulls. Sometime hopefully within the next month or two I will do a final light and electrical test before cementing the hulls together and putting the bridge and top lid on the build. I know I have some light leaks from the engine bell fittings that I recently affixed and I am thinking about how I am going to deal with that problem.
Seeing the light at the end of the longest build I have ever done. A little bit at a time so the tedium does not wear me out.