[Repeater-Builder] Pair of GM300 as a repeater

[la88y]

I'm wondering about the suitability of a pair of VHF GM300s as a repeater. Is 
the shielding sufficient to allow 600 kHz between Rx and Tx? If not, what is 
the suggested minimum? 

Same questions for UHF SM50, but with a 5 mHz split?

lh