I think there are a total of 5 zerk fittings on the car;
(3) 14mm u-joints--on the steering (near the coupling joint), and on the shift linkage (in the tunnel right behind the shifter and the other near the input to the ZF).
(2) others on the drive shafts (?)
The Fiamm country horn compressor is another likely maintenance point...but then, I think for a 50 year old Mangusta its all about "re-lubrication..." (and replacing what is there, that at one time could be called "grease). The grease in the window motor transmission and in the steering rack hardens after a few decades (where well, probably cannot act as lubrication !) and the rubber dust caps for the Heim joints used everywhere on the suspension harden and crack open. Pulling these off and clean/re-booting is not a bad project in itself...
Of course, bearings become another story, with the only ones 'easy' to swap are the front wheels...Lee