Don't really need an A/F gage.
Assuming this is mostly a highway drive to work.
Increase the restriction on primary side main circuits - one step at a time.
Test it to make sure its still drivable. If so, take it to work.
Repeat until it too lean (you'll know - it will be undrivable at interstate speeds)
Go back to a less restrictive rod or rod/jet combo.
If you want to buy vacuum gage, that's nice tool to have, relatively cheap, and can help your driving habits too.
Use the drag strip best mph to determine the jetting. Work the opposite direction, go richer as the first tests.
Finally you can experiment with the step up spring. Car should go leaner and faster with more pedal until some point over half throttle. Then it needs enrichment or it won't accelerate. There will be a dead spot. vacuum gage is a useful reference tool, but again not neccessary. Performance is the measurement that determines the best tune.
