You might have a significant difference in spring height as well as load carrying ability - for example, I had a mid seventies I-6 Granada. I purchased an identical car, but V8 version from a friend. This car had just had a complete front end rebuild including springs (he blew the diff. and had just too many other repairs and wanted to get rid of it - cheap). Mine needed that front end - including the springs so I unbolted everything and moved to mine. Wow - the front end with V8 springs - way too high - I ended up cutting about a coil and a wee bit more for ride height. In your case, might be way too low plus too soft for the V8 and you can't "add" a coil.

Another case - my '31 had 160# coils supplied by TCI in the front - way too light which meant I had to crank the adjusters almost to the end of their threads to level out the lower 'A' arms. Now, I have 300# springs and the adjuster is up about an inch for level 'A' arms.

Get the springs to match the engine - or face doing the job again and these Falcon/Comet chassis cars with McPherson strut suspension are not a fun project with a spring compressor and minimal working room.