Nice work!
I'm thinking Yamaha should have angled the carb just a little more to the side to clear the shock, and have a more unrestricted path for the airbox boot. Just a few more degrees to the side..
I'm soon getting to this problem with my DT230 conversion, and I ordered a CR125 intake (same size as DT230, CR125 VF reed is bolt on) to see how that aims the carb.
The intake that came with the engine has a too large connection for the carbs I intend to try, but inner diameter is only abt 31mm, so really suitable for a 30mm carb. I also ordered another 'stock' intake that hopefully has the correct diameter for my carbs. There are two versions, and I got the one with the larger diameter carbs with the engine.