My SLP-98 is upgraded, partially by myself, and originally from Cary with better parts than the old Upscale F1 upgrade from a decade ago. Here is my recommendation, fwiw. If you are not sure, stop here and send it to a well practiced tech with proper measurement equipment. It's not just about slapping in parts and crossing your fingers. There are other things they can check while they have it open. It will be totally worth it if the tech knows what they are doing.
@dpm2340 hoping you chose the right parts for max benefit and reliability. If you get stuck and need a good tech, I might know of someone to recommend via DM/PM privately. The 98 is totally worth upgrading if done properly. Best of luck.