Foreign valve springs in a Magnum

What heads did you buy? Stock Magnum? Iron Ram/EQ?

There is no adjusting the lash on stock Magnum rockers, you just torque it down to 20 ft lbs.

Hughes' 1110 valve spring should be more than sufficient for your camshaft. If you have the heads off, I'd get the pockets machined for taller springs.It opens up the possibilities immensely.