Oops, sorry for the slow response......
Anyway, 5-6 weeks sounds great, but I sincerely doubt that he can get that much time off. So can this time be reduced by:
1: Doing the ground school in a foreign land with a FAA AGI and getting signed off for it? (Part 61)
2: Doing the written exams before arrival?
As for the weather, I'm suggesting some school on the west coast of Florida around April.
Cheers.
Mutt