Actual timetable for going from 6.1 to 8.0x.... Input please

This year we're going to 8.0. Ours won't be the typical upgrade. I have customizations to our source code(We're one of few that had source for Vantage up to 6.1) and some customizations to our Database custom tables and such(YES I KNOW, BUT I INHERITED THEM FROM MY PREDISESOR ).

My big question for everyone here is what was your actual timetable for going from 6.1 to 8.0x? Did you have in special scenarios to overcome(ie source code customizations or DB customizations)? I would really like more than "it took 10 months" . Something along the lines of "so many weeks of this", "so many months for that".

How many months of Training(# of users)?
How long did DB conversions take(size of DB)?

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