Howdy
If you want the best hollow ground screwdrivers, Brownells Magna-Tips are the best. If you manage to break or bend the tip off of one, they will send you a replacement free of charge. No other brand does that.
https://www.brownells.com/gunsmith-.../magna-tip-sets/magna-tip-sets-prod41571.aspx
I have a fairly extensive set that I have accumulated over the years, you don't necessarily need this many. You can select what you need from the web page I posted above. Be sure to use a bit that completely fills the slot. Buy a few if you are not sure, they are worth it. Buy the standard screwdriver body that you see in my photo to go with your bits.
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All the above methods are good.
The lever screw on most lever guns sits in a threaded through hole, meaning the hole goes all the way through the frame. When applying penetrating fluid, Kroil is the best, be sure to apply it at the screw head and to the threads at the end of the through hole. Give the Kroil time to work. Apply it, then set the gun aside and allow the Kroil to work over night.
I use the Brownell's gunsmith screwdrivers also. In over 30 years of part-time gunsmithing, I don't recall ever breaking a tip.