Rear Water Pump Grease Fitting

[Colonel Biggs]

What is the latest assessment of the type of lubricant to use for the rear fitting? Bratton's advertises a low-temp grease, which presumably will dissolve
if it makes it to the radiator, while Snyder's advertises a high-temp grease.

And, for the rear shackles, I suppose that there is no way to force the grease into the shackle itself without disassembling them.

Thanks for any thoughts.