new high pressure oil pump - no gasket between block & pump, right?

[BB73Challenger]

Hi guys -

The reason I ask is, I'm getting a huge oil leak on the bottom of the engine up front!

I wanted to up my oil pressure and opted for a new Meling high pressure pump.
It came with no gaskets, as well as the old pump appeared to not have any gasket material between them.

Now there was an o-ring on the shaft of the oil pump, the old one it was brittle and cracked as I tried to remove it.
I simply dug through my pile of extras and came up with an old gasket set that appeared to have the necessary o-ring, as it appeared no one in the local auto part stores could even get me one.

Now I believe this mess coming from the increased oil pressure, but something like a timing chain seal would not reflect the increased oil pressure, right.
That would be for the "closed" oiling system like bearings, right?

I was curious if I was missing something on this new oil pump since it wasn't a problem till I made the switch.

Any input is greatly appreciated as always, Thanks!!

[Changin Gears]

Big blocks have a gasket between the pump and the block.

[BB73Challenger]

Big blocks have a gasket between the pump and the block.

That would explain alot - thanks.