@yagigain - Stephen,
The original HF Mod involved the coils MN18 and/or MN26 to be removed to obtain HF capability with the LimeSDR.
There’s also a link here to show how to modify the Wideband Port, too:
Hope this additional information helps - keep me advised if you need any more info on this, Stephen,
73 de Marty, KN0CK