Hi greggster,
This unit would have been delivered to HD 99% assembled if not 100%.
Generally the throttle and choke levers are the same cable travel wise. When there is more lever travel than the engine needs, the manufacturers will adjust the cables so that when full throttle or full choke is reached , the inner cable will bend somewhat allowing the levers to reach to the full throw.
I recently repowered my Scag Tiger Cub with a new 30 HP briggs from a 2007 26 HP Briggs. The throttle on the new engine needed about 2/3rds of the cable run as compared to the old engine. Adjusting this cable to the bending situation was too much so I installed a metal bar across the throttle lever opening to stop the lever at the low idle position. The choke on both engines had the same amount of cable run, but I adjusted it so that it got to full choke before reaching the lever limit and full open when it is at the other limit.
I would still take your new machine to a servicing Toro dealer and have them deal with this problem.
I expect that in time, the throttle and choke levers will be changed or more cable holes will be drilled to allow an adjustment to be selected to change the of movement that the cable travels to better accomodate the needs of the engines.
I had considered removing the levers on my Scag and drilling a hole closer to the pivot to reduce the amount of cable travel, but the diameter of the pivot pin was a problem and would bend the cable every time I pulled the throttle back to low idle.
Mad Mackie in CT