I use wheel bearing grease. I have noticed that really early pedal assemblies (no pedal pivot) have zerk fittings so I suspect that front end grease is also OK.
Yeah some may call it overkill, but you can't have too much overkill.
You'd just need to drill & tap a hole in the top of the casting for the zerk, with a small hole going through the steel tube to get grease to the clutch shaft. A second hole in the tube outboard of the casting will let grease come out to reach the brake pedal. A 90° zerk can make for easier access. For a street rig, you shouldn't need to do this - wheel bearing grease should be sufficient for about 10 years....