Bear in mind that if your body bushings are shot you will have to make some room with a 4 lb hammer to clear the coil.
I am using an Accel Supercoil equiped HEI and I had to stretch the firewall a bit to get it to clear.
But my body mounts are wasted and need replaced. With new bushings and a 1" body lift it won't be an issue any longer.
Yeah I know it's a mess under there. It's one of many things to do on the list.