[Yaesu] FT-990 Low Rx sensitivity after high dose of RF while QRV SO2R

[N6EU]

While operating two radio in a recent RTTY contest and not paying attention managed to over expose my #2 radio
with RF.  Symptoms are weak RX.  TX and all other functions appear to be normal.  No obvious damage.  I really like
this radio and want to reapair it my self.

Anyone have any experience with a similar problem?  I talked with Yeasu today and a new RF board is just shy of $300.
The extender board set is at $285.  I am fairly confident that the faulty components are on this board but not completley sure.  The signal path through the band pass filters on this board is fairly complex.  Any help or ideas would be greatly appreciated.

73 Russell N6EU