[CQ-Contest] CQ WPX Serial numbers for M/M with two transmitters on a band

[Larry - K7SV]

I'm looking for anyone who has done M/M with two transmitters on a band in 
the CQ WPX contests. The problem we're realizing is serial numbers. Separate 
serial number sequences are used on each band for multis. If we have two 
transmitters (interlocked so only one may transmit at a time) and we're 
using two computers, we end up with two strings of serial numbers on the 
band. Anyone else wrestled with this?

73 de Larry K7SV