Need help with lock post replacement

[Sean F]

I need to replace a lock post as part of my restoration, but can't find any spot welds on the quarter lip. I see them on the interior, but not the exterior. I've ground as much material off as I feel safe doing and tried a torch to see if they're hidden with lead but no success. Now I'm not sure what the right way to do the replacement is. Here is how it looks:

[Sean F]

I found these pictures of someone's install and it looks like the spot welds should be drilled from the outside:

[jonnyw]

I would take an abrasive wire wheel to the lip shown. The quarter curves around and lays over the door stricker plate.

One of those wire wheels usually scrape enough metal off the lip so you can see the spot welds. From the picture it doesn't look like you've cleaned the area enough.

There is also lead in that area so if you do break out the wire wheel make sure to wear a good mask.