By restriction I guess you mean the brass reducer on the intake into the old filter
No, that's not what he means. There must be a restrictor installed in the return line that reduces the flow through the spin-on filter to avoid starving the engine for oil. I use a Holley carburetor jet drilled out to a 1/16" diameter orfice, threaded into the reducer bushing for the return line. A 1/4-28 thread is close enough to allow the jet to be threaded into the reducer bushing.
Jerry