MTH railtown structure wire gauges

Hi Everyone and Happy New Year.

I have several of MTH's structures that I will be wiring to my O Gauge layout.

I most cases I need to extend the 2 wires for each unit to the terminal block and the AIU.

It seems the existing wires ate about 18 or so gauge. Since I have a spool of 16 gauge wire

is there any issues using it to extend the structure wires? Since these units are just lights,

I am not sure if I want to wire them to the AIU and rather just wire them to a terminal block

and power it with a Z-500 or so. Any input on this as well.

Thanks very much,

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