sorry, but i'm not sure what the exact differences are between the 600 and 700 series engines.
the blades/head and transmission are all the same as the BA/B2 pretty much except for the tail which has the B3 box and blades. i do seem to recall that if you have an existing airframe that is to be converted there are some structural mods that need to be completed. i suppose that makes sense as with the -700 engine installed the MAUW can be increased to that of the B3, however this results in component having B3 o/h times being imposed upon them.
keep in mind that i am not an engineer just a lowly driver and stand to be corrected on some of the details
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