Sounds good, the needle rollers shouldn't need too much oil. Ironically I was just musing over your proposed mod and scribbled a layout to check for correct rotation. I came up with exactly the same for a gear wheel count of seven.
Since this would (maybe) allow you to use existing idler pivots, is this what you intend?
Is it possible I wonder if S & S originally designed engine with geared timing as an option.
Not sure where scavenge pump sucks from - where the most oil is I guess.
