I cut the front springs on my '63 using a small angle grinder, and there were no problems.
The springs sit in the little recess in the control arm. No other modifications were done, and the car now sits at the perfect height that I wanted.

As a general rule, for every inch you cut at the spring, it's about double that at the wheel.

Here's what mine looks like with 3" lowering at the front and about 2 1/2" at the rear.

Just remember that if you are measuring for height at the wheel, you need to make the spring measurement in it's compressed state with the weight of the car on it.
Then when the spring is removed, cut it.

Thanks for the compliments on mine. 

I sat the car on level ground and measured from the ground to the underside of the chassis.
I then decided how much I wanted the car lowered. I also removed all the wheels and lowered the car on trolley jacks to the height that I thought looked good and suited me.

I removed the rear leaf springs and took them into a suspension shop and got them to re-set them approx 2 1/2" to 3" lower. Once they were fitted back into the car, I could then see how much the front needed lowering to get it to look right. If I remember right, it was about 1 coil, but you'd have to do your checks.

There is absolutely no rubbing anywhere on my car. This is with 15" wheels, and 75 profile tyres.

Last edited by 63gal427 (February 22, 2013 6:35 pm)

I assume you guys are using the stock springs? Are you using new replacement springs or the old oringal ones that came on the car? Do you know if these springs are a linear rate or progessive? Im curious because I am in the process of getting a '66 and the front end is VERY soft, too soft. I already know Im going to get new shocks, but I would also like to get springs. The car has a small block and I will most likely keep it as such. I may try using big block springs if I can determine they offer a heavier spring rate.