Cheap & DIY - you'll fit right in.
(Substitute "resourceful" for "cheap" if it offends.)
Nice HF! I'm jealous.
You should definitely get yourself an MPGuino - instant MPG feedback & resettable trip MPG will go a long way to help adjust the nut behind the wheel. Oh wait... this is carbureted, isn't it? Hmm. Might be out of luck there.
Also for relatively subtle & inexpensive mods, consider: partial grille block; smooth DIY wheel covers (full disc); lower the car an inch or 2.