I hear you on the handling and braking of these old cars,I've been driving them forever. That said there are a ton of things that can be done these days to them without having to cut out the shocktowers to improve the braking and handling. I believe the first guys that did the Mustang II Conversions did it to get disc brakes as well as to get some room in the compartment for a big block? That said I prefer the stock look, But every car that I have has improved suspension(roller spring perches,higher rate springs,quick ratio steering boxes, larger sway bars,etc.), and most have better brakes as well. If your wallet is deep enough you can go crazy with a couple of the companies I told you about plus others like Total control products,SSBC,Scarebird,etc. It's really all a matter of how far you want to go $ wise.