nice mod Alan,
i happened to buy a dremel 4000 and a fein multimaster 2 weeks ago, and but them buth in the same sys 1 with lid compartment.
I don't have an extended range of accs, so they all fit loosely in the lid compartment, and both tools fit nicely below. Came in real handy last week when i installed some stair thread covers.
I plan on making a proper inner division insert, i will certainly steal some ideas here.