Dave is right, to try and use something like a pillar drill and get it right is probably more luck than judgement and there isn’t much wriggle room to play with.
A good machine shop can do the job but you would need to provide the correct data on where a new bush needs to be and where the new axle holes have to be machined to get the correct mesh on gear wheel and armature worm.
This has been my life saver for later diesel chassis and it has never let me down. Even used it on Lionel chassis.
