You should not have to remove the mag tube to take out the bolt. You might have to loosen the stock bolt, as I have seen them so in so tight, that they bind the main take down screw from easily coming out. In other word, the wood is pushing against the receiver, and in effect causing the lever group to pull against the take down screw. Hard to explain but I am not making it up.
The stock and trigger group will then seperate from the reciever and the receiver will be like an empty shell. It may take some gentle twisting and wiggling to get them to separate, but just don't force anything ,or be tempted to get a hammer.
As I recall, the bolt will,then be in hand, and upon re assy, may take some patience getting everything lined up back into place.
Seems like the ejector just lays in a groove on the left side, so find a nice clean bench, or hardwood floor, so that ya can find it after it falls out. Might be wrong on the ejector, it has been a awhile since working on one. And if memory serves, the tube is held in by the cross pin through the for end band, but again, little reason to ever drive it out in such a case as this.