Hey Doc,
I'm thinkin that if you modify the ejector to contact the case later in the stroke, it will interfere with the round on the carrier. And ifn your running your rifle fast, that empty needs to get out of the port area in order for the next round to move up on the carrier without any interference.
As soon as I get time, I'm gona experiment with moving the ejector forward just alittle to see if that will enhance a rearward ejection of empty brass.
Others:
With some success, I've managed to get a couple Marlins in .38 to eject at 90 degrees from the port and not forward. It all had to do with how close the purtruding portion of the ejector (the part that extends beyond the 'hump') was to the side of the case when the rim made contact with the 'hump'.
From the two I've worked on, I deepened the channel in the bolt area that slides back and forth over the ejector and allowed just alittle more of the rim to make contact with the ejector 'hump'. This also put the forward portion of the ejector real close to the case and was useful in helping to flip the case at 90 degrees.
I also slightly (very slightly) angled the stopping edge of the hump backwards. When I say 'slightly', I mean its hardly noticable.
I haven't experimented with this technique enough to say it will work for you so proceed with caution and make sure you have an extra ejector available just in case this don't work for you.
Good luck.
..........Widder