i i have a wagner wm 3 loader on a 1949 ford 9n with the dirt bucket and would like to make a extender for the bucket so i can holf more mulch and snow how deep should i make the sides thanks thad

I had a WM3 on my 8N and I widened the bucket 12" on each side. I did make it less deep so that I could not overload it with dirt, etc. My purpose was to be able to scrape dirt and snow and have the front wheels not trying to push snow or dirt and to stay level. For leaves and mulch you can probably make it deeper by extending the sides and cutting edge forward BUT, someone could overload it with dirt and get into trouble like filling it too full, raising it too high or even breaking the front axle (not a pretty sight and VERY costly). You have to be the judge and decision maker.
For leaves and mulch I had an extension that would slide into/onto the bucket and bolt to the sides (sorry, never took any pics) Be safe, whatever you decide.