The lower baffle will help. It helps guide the airflow through the radiator, rather than around it. Shroud, upper filler pieces, lower baffle, masticated fillers are all part of the package.
A/C on a 'vert is nice when not moving fast enough to make a breeze (cruises). I find that the clutch fan moves enough air for even low speed cooling on my 400.
Vikki 1969 Goldenrod Yellow / black 400 convertible numbers matching