How to convert Class A/B amp to pure Class A

Hi. I own a wonderful Threshold Forte Model 3 solid-state amp. It is a Class A/B design that is rated at 200 wpc into 8 ohms. I have read that it is essentially the same amp as the Model 1A, which is a pure Class A amp rated @ 50 wpc, and that it is fairly easy to convert the 3A to the pure class A configuration (and consequently drop the power output to 50 wpc). I am fairly handy; anyone have any suggestions? I have read that constructing a brass or copper rectangular plate to connect the inner-most screw lugs of the 4 big caps is a good start. Any suggestions? Many thanks.