I am attempting to remove and replace the bottom bracket from a cheapish 1970s American department store road bike. I've gotten the lockring off, and now the non-drive side looks like this:
The situation on the non-drive side is similar, but the only photo I have right now is slightly less clear:
That photo's from a few days ago and I have since gotten the lockring off the usual way. What's the tool or technique that will let me get the bottom bracket cup itself out? My shop doesn't have a bottom bracket tool with notches like this, nor have I seen one online. I tried a pin spanner to no avail. It's difficult to see in the photos, but the sides of the notches in the BB are somewhat sloped, so the pins don't get any "grab" and just slide right out when I start to turn them.
That's what I've tried so far. What am I missing, or what else can I try?