Jack points on a '30

This may be a dumb question, but I want to be certain about it. I assume it is okay to jack up a '30 Buick from the differential, aka "pumpkin", to get the rear in the air. And the front can be done by placing a jack under the cross-member. After years of being told to use graphite to lubricate locks, I was told by a locksmith that was a bad idea. Now I'm starting to question other things I knew to be "fact".

Thanks

Concerning jack points, it's probably safe to say that any passenger vehicle is OK to jack up by the pumpkin. But in the case of my '30 44-series roadster, the drain plug protrudes from the bottom of the housing, and I certainly don't like the idea of all that lifting force being applied to the plug. So, whenever I jack the car by the pumpkin, I place a block of wood (ordinary pine) on the jack pad. Soft enough for the plug to sink into it, the block properly spreads the load across the bottom of the housing.

Thanks. I have the same issue with the plug but I'm glad to know the pumpkin can handle the weight.

Concerning jack points, it's probably safe to say that any passenger vehicle is OK to jack up by the pumpkin. But in the case of my '30 44-series roadster, the drain plug protrudes from the bottom of the housing, and I certainly don't like the idea of all that lifting force being applied to the plug. So, whenever I jack the car by the pumpkin, I place a block of wood (ordinary pine) on the jack pad. Soft enough for the plug to sink into it, the block properly spreads the load across the bottom of the housing.