This is the most ghetto thing I will ever admit to having done, but:

I bought a lump of plastic "clay" at Michael's, mixed in two cotton balls for reinforcement, molded it onto the front sight for really solid support, then baked it.

Drilled for pin clearance, then went to town with Kroil, a nail punch, and 5 pound sledge, with the support jig on the garage floor. Two hits per pin and I was done, compared to an afternoon of pounding on my workbench.

Whether this is a testament to the shittiness of my bench or the utility of improvised tools, I don't know.

Total cost of "jig": $1 (+dignity)