1930 standard sports coupe ........ wiper ?

[headonz]

I have just replaced the wooden windscreen frame that came with the car with a correct metal frame . Now I want to replace the motor with a after market 6v model.

How was the original w/m attached ? inside or outside ?
I understand I could drill through the header but the shaft on the original v/motor and replacement 6v motor does not seem long enough to accommodate this ?? What am I missing ?