The xt crank shouldn't be 83mm axle, these axles tended to come on cranks for DH use iirc.
If the spacers are correct on the BB, and it is a 68 not 73, I can see only 2 issues.
1. The cranks are not sitting right in the BB and need to be pushed through further.
2. The front mech limit screws need adjusting to allow it to travel further up over the big ring, and of course the reverse so you don't drop a chain all the time when dropping to the granny ring.
Have you tried loosening the limit screws to get more travel on the mech? Will only take seconds to verify and you don't even need to connect a cable to test.
If the spacers are correct on the BB, and it is a 68 not 73, I can see only 2 issues.
1. The cranks are not sitting right in the BB and need to be pushed through further.
2. The front mech limit screws need adjusting to allow it to travel further up over the big ring, and of course the reverse so you don't drop a chain all the time when dropping to the granny ring.
Have you tried loosening the limit screws to get more travel on the mech? Will only take seconds to verify and you don't even need to connect a cable to test.
