Go with what makes you comfortable stopping it. If it's scary getting it stopped you will never enjoy driving it. I'm not sure a booster is the answer though, It has stopped with what it came with for nearly 50 years with no problem (assuming it's not all wrecked).

1953 Chevrolet 3600
Fried Green T'mater (Vern)
In the Stovebolt Gallery
Caution: Political Statement
Man who runs in front of car gets tired, man who runs behind car gets exhausted.