The original P3a by ESP used those transistors and gave out 100watts in 4 ohms. If you are sure yours are not fakes then why not try his circuit. See: < 60-80W Power Amplifier >. He also sells you PCBs if you want them. They have 2 circuits on one board but can be cut in half.
BTW your link in your edit, doesnt work.
Tony![]()