Location of engine earth lead

Dear readers,
To solve an issue with low charging voltage of my battery, I want to have a closer look at the engine earth lead.
The earth of the battery is connected to the chassis, and the alternator also has an earth connection, by means of the engine earth lead.
Where can I find this engine earth lead ?
Thanks
Kind regards
Theo

That gives you the engine earth lead start point. just a case of actually getting to it. between the exhaust manifold and the firewall.

Most issues are with the battery earth point though. Take it off and give it a good de-crap. That solved my intermittent starting problems. ie, sometimes wouldn't turn over enough to start the car despite a fully charged battery!

I would agree with David the battery earth point can be very troublesome. I swapped the bolt that goes into the bulkhead, to earth the battery, for a stainless one and my car wouldn't work at all. I had to put the rusty steel one back in to get power to my car.