Found a bravo 1 drive but the guy said it was any where from a 2002 to 2005 model. Is there any differnce in those years?

The sweptback upper was introduced in 2005. Smoother shifting. If you have a serial number you can determine the exact year.

looks like 0l737452

Based on the serial number its a 96-99 model. Anything special to know about those years? I did find a couple 1.5 ratio drives for alot less. How hard is it change out to 1.65 & roughly what would it cost?

The OL's had the thin floored gears. A new gear kit for X-gears (changing it in the upper) is around $1650. Then you have labor to set them up and some shims also.. figure another $350. That would replace all the parts in the upper. Then you have to look at bearings and gears in the lower.
Hope that helps.
Dick