Here is a little write up on how to do this.
First find out how wide your slide is each one is going to vary some. Now source a clamp that is wide enough to give you at least a little clearance and has a web at the top thick enough to support a threaded hole.
I have access to a lathe and mill this makes it a lot simpler for me. But if you have a drill press you should have no issue I will explain how.
First find a brass screw that is long enough I used a 1/4" 20 tpi that is 2" long. I think I would actually make it a #12 to help next time to give it a little more clearance on the sight groove.
I milled a flat spot in the top of the clamp to make centering and drilling easier. Careful use of a file will get the same results.
Now I drilled and tapped the hole for the brass bolt. Use tap drill chart for the size and pitch you are using.
I turned the tip of the bolt down in the lathe to remove the threads from the end as well as faced off the end to make it square.
This can also be done with the use of a file. I would mount the bolt in the chuck of the drill press and let it spin as you file off the required amount.
The clamp I used was just hardly big enough to fit the slide so I milled the contact point off a few thou this also made sure it was flat. Something else that can be done with a file. If required
I used brass shim stock to protect the slide. A soft protector like rubber may cause your clamp to wiggle slightly when you put a load on it this will cause it to come out of alignment with the sight while pushing it.
When using the pusher make sure to put some grease on the tip of the screw where it contacts the sight to reduce friction. I had a little bit of brass transfer to the the sight but it was quite easy to remove with some gun cleaner.
If there are anymore questions feel free to ask I hope I have it all covered.
