I use a little different approach with my 650. I just leave the small primer feed mechanism in place. I load GI ammo boxes full of 9mm and 223 in a given session so I absolutely need the small primer feed assy. Changing the shell plate is no big deal and unlike a lawnmower blade you referenced, the shell plate isn't covered with green goo mixed with doggy doo
When I load large batches of .308 I prefer to prep all the cases in advance to include priming. When the time comes to load I just fill the case feeder with the sized, trimmed, and primed, brass. When it passes over the primer station it doesn't even notice that the punch is small. To make sure that the case is aligned in Station 1 I use an extra powder die body that's screwed down to touch the plate when the ram is up. This makes sure that the plate isn't cocked, even slightly, when seating bullets and OAL variations (measured to ogive with a comparator) are as consistent as when loaded on a single stage.
Another press offered by Dillon but not often discussed is their basic 550. A stripped 550 that you can upgrade at a later date without having to buy a new core press. For someone on a budget it allows them to get started and then add more features "at tax refund time"