Originally Posted by jnanian
see if you can contact the person who posted the photographs of his 3x4 to 4x5 conversion here
he said it took him 20 mins and it was not difficult
good luck !
Putting a 4x5 back on the 3x4 will allow you to use 4x5 film. It will not cover the entire sheet of film though.
In my opinion it butchers the 3x4, while not functioning properly.