If you have a decent set of brass punches and a small brass hammer it takes about 10 minutes to install and is pretty easy.
Here's a link for disassembly
Model 41 maintenance
Basically you remove the cross pin, tap the hammer block forward and the extractor drops out. I spent some time cleaning while I had it apart. I also blew a to of gun cleaner in the hole that houses the extractor plunger, mine didn't fall out like they show in the maintenance however the stroke of the plunger was a little gritty so I cleaned and oiled it, this may also help in extraction.