Alt Adjustment '75 240D Bosch PES4M55C320RS58 Inj Pump

[Fisherman]

Quickly I would like to ask if anyone is aware of a manual adjustment for this pump or if the altitude compensation is automatic and if so by what mechanism.
Driving at sea level the car runs very well with no smoke at all visible, even under heavy load.
At 3200 feet and higher the car smokes quite a bit while still performing well.
I understand that on the later models this adjustment is located under the ALDA on the top of the IP however this IP does not have an alda on the top so it is assumed that it is controlled by another means. perhaps the vacuum line connecting to the rear of the IP?
Any light you can shed on the adjustment mechanism would be greatly appreciated as I am certain it is not correctly setup at this time or is not functioning corrrectly