New to me 1993 300e 2.8L

[Paulhorner]

Hello.
Just acquired 1993 300E 2.8 L.
Blower motor is running on low speed only regardless of fan or temp setting.
Getting cold air but very little of it.
Can anyone suggest any fix other than a frightfully expensive blower motor regulator?

Also with ac on full it is prone to overheating with no high speed action from the aux fans. Ceramic resistor behind driver headlight would supply low speed power only??

Anyone think these two ailments are related??
I have not checked the amount of refrigerant in the system. Would topping up refrigerant effect either issue.

One last thing I understand this model used 34a but the connectors are the larger couplings that is commonly on R12 systems. Could be a transition year and they used the old fittings with the new gas???

Thanks