[Amps] Keying the LK550ZC

[Hugh Phillips - K7XM]

I have a LK550ZC, using a IC-7000 as the exciter.  Is there a 
work-a-round to key the LK550ZC with the IC-7000 using QSK so as to 
utilize the keyer in the 7000?
According to the amp manual, for QSK to work, the amp has to be keyed 
first, then to the exciter. However there's only a two conductor RCA 
input and then the same for the out to the exciter for the keying line.

Has anyone modified this amp so as to utilize QSK keying through the amp?

TIA
Hugh,
K7XM