shortening the pushrod side: easiest and most common
is there another method: completely new rocker, keep the stock lever total length to retain vertical alignment with the stem and pushrod, but move the shaft toward the pushrods

E.g. my current project:
Total effective rocker arm length, adjuster to pallet: 3.40625"
Pushrod lever 1.375"
Valve lever 2.03125"
Ratio 1.477:1

New rocker with .158" offset center barrel:
Total effective length: 3.40625" (same)
Pushrod lever 1.2165"
Valve lever 2.1900"
Ratio 1.8:1