Magnum Head Valve Spring Compressor

Getting ready to do a cam swap on my Magnum headed 360 and have to upgrade the valve springs. Really don't want to pull the heads to upgrade the springs.

Current springs should be P5249464 based on what I have found online to have come on the MP R/T heads I am running. Swapping to the P4876062 spring.

The P4876062 spring has a dampener, not sure on the P5249464 spring.

Because it has a dampener, don't think I can use the screw type compressor. And the stud mount compressors all say for 3/8" or 7/16" studs, but the Magnum heads have a 5/16" studs (as I recall).

Anyone have any experience and/or input as to what tool I need to do the job?