[RAS]

I plan to install couple of spot lights behind the soffit and cut holes just for the light to protrude out and point at the house number.
I have no trim cover to hide any inaccurate cut.
What is the best way to cut the hole?
Thanks much in advance for the answer.

 

[oh'mike]

A nibbler----Kind of like a paper punch with power---tin snips work but might distort the thin metal.

A center cutting snip will also do--it has two fixed anvils with a cutter in between. It removes a 1/8" wide ribbon of metal.

 

[DexterII]

Not sure exactly what you have in mind, although I have a general idea, but you'll want something to keep squirrels, bats, wasps, etc. out of there.

 

[RickyBobby]

A hole saw in reverse could also do it.