I have a 69 Mach 1 that drives well. It steers straight, doesn't wander and handles bumps well even at speed but it has a "give" in the front end as you put on the brakes to stop. What might be causing this?
Since virtually all suspension components are rubber bushed, there will always be some 'give'. If it is that noticeable, and if the suspension has never had a complete rebuild since new, odds are all the components are worn out and in need of rebuild.