Hi Bob, we both have v similar machines. I got the slightly bigger 7491 version.
I can understand the need to sometimes remove the crown guard (and it's built in RK) for ripping narrow pieces less than 2.5cm but I don't know why you can't install the standalone RK. I've never needed to remove that for anything.
One thing I haven't seen mentioned (apologies if I'm wrong) is the length of the piece you're trying to rip, if it's too short I think it might be too hard/dangerous to control.
If you're trimming small pieces I wonder if you're better off making a crosscut sled Bob.
I can understand the need to sometimes remove the crown guard (and it's built in RK) for ripping narrow pieces less than 2.5cm but I don't know why you can't install the standalone RK. I've never needed to remove that for anything.
One thing I haven't seen mentioned (apologies if I'm wrong) is the length of the piece you're trying to rip, if it's too short I think it might be too hard/dangerous to control.
If you're trimming small pieces I wonder if you're better off making a crosscut sled Bob.