I need to remove the front sight from my Henry SXS. There is a notch across the base in front if the blade which I assume is for tapping out the sight but I tried a couple times and it won't budge. I haven't hit hard as I don't want to mess something g up and don't really have anything other than a small screwdriver to engage the notch. Hopefully it is not soldered in place. Any suggestions how to engage the notch to drive the sight out?.

Licensed to Kill,
It would be helpful if you post a photo. A general protocol is dovetailed items enter from right to left and are removed from left to right. This is not a law, so check first, if you can. Also check for a screw, pin, or spring loaded plunger.
Mike

If your front site dovetail is in line with the bores, then it is a friction fit. Some have a screw on the end of the muzzle to keep the front site from coming out upon recoil.

Sorry, I assumed that all double rifles from this era would be similar. This is what I am working with. There is a cross-notch just in front of the blade that assume it for driving the sight out.

Licensed to kill,
If you apply pressure to the small piece behind the "cross notch" and if it moves, as if under spring pressure, it may be a device to keep the front sight in place. In either case, you remove the sight by driving it toward the muzzle with a non marring punch in the "cross notch". If piece behind the sight does move, hold it down while driving the sight out (at least until it starts moving). Good luck.
Mike

That one will drive straight forward towards the muzzle. You may drip a little penetrating oil on it for a day or two first.
I filed up quite a few of those caterpillar front sights in my time at the bench.
Absolutely cannot stand those commercially available ones. They simply do not look correct on a fine antique rifle.