I have a Savage-Fox BSE in .410. The first one I owned was purchased new in the mid '80's for around $300. I traded it rather abruptly for an imminently forgettable gun that has long since gone down the road.
I found one in new condition earlier this year and, for 4 times the money, I was able to replace the one traded in haste. I didn't get a manual with this one and have a question that could, no doubt, be found with one. The top lever in all these guns wants to head toward 8 o'clock. There is an adjustment screw on the barrels that I think can be used to prevent this from happening. Is this correct?
If not, what, if anything, can be done to keep the top lever at or to the right of center?

so long as the gun locks up tight, why make a big deal about the lever...and do the barrels ring to your satisfaction?

It is a neat little gun...not an heirloom, but I like having it around. I could have spent $4,400 and had a set of .410 barrels fitted to my A-10. At some point, sanity prevailed.
The trigger pulls were so bad (8&10lbs)with a ton of creep,that I had to send the gun to Gunter Pfrommer for extensive work.
I got it back yesterday and immediately took it to the skeet range. It shoots great now and I hit what I aim at. That is what it's all about. It may be the red-headed stepchild in my arsenal, but it's a keeper.
As for the top lever, there is an adjustment screw on the barrels and I've forgotten what it's for. I think the Model 21 has a similar setup. My top lever is at 6 o'clock now but I am curious as to what others do when this is not the case.

As the bolt wears the screw in a 21 is turned in to allow it to seat deeper which also allows the lever to go further left. If you use that screw to center the lever then the bbls won't bolt up tight. I din't have a Fox model B but I didn't recall they had an adjustment. They use a wedge shaped bolt locking in the top rib extension & as the bolt wears in the wedge goes deeper thus the lever comes around further. As a general rule, there are a few exceptions, on a gun with compensating bolts as the bolts wear the lever comes around further, that's how they were designed.

I don't recall any adjustment screw on the BSE. If you're looking at that phillips screw at the very top breech end of the vent rib, it just holds the rib to the bbl assembly.
I can't think of any other screw in there but they made a number of different series of these with different changes.

The locking wedge is part of the top lever itself. All one part. These are actually 311 actions.

Sometimes the top lever is removed from the action and the hook given a little wack on a lead block to bend it downward a slight amount. That makes it engage the bbl rib extension quicker and in turn brings the lever over 'right of center'.
Sometimes it's done with the lever still in the gun.
It's for looks only anyway. Not a fix, just a cosmetic fix'er up.
If overdone can cause a sticky, hard to open top lever too.

It's a selling point issue and used for resale of guns alot (lever position). It really makes no difference on the guns as long as they are on face, locked up securely and still some take up available in the system when secured.