[Hutch]

I think it is a good swap.
You might get away with just an axle swap for the rear. (Depending on your year model)
One reason to keep it six lugs is: if you already have a substantial investment in your current wheels.
There is a good supply of the Chevrolet Rally wheels available in both six and five lug in the 15x8 size. Check at the local swap meets.
If you like the larger diameter wheels then 5 lugs is the way to go.
Some members have just had their six-lug rear axles plugged and redrilled for the 5 on 5-lug pattern.
Front rotors are less expensive in the more generic 5-lug variety.
Don't forget the spare you never know when you will need it.
Overall it makes good sense to go with the 5-lug swap.

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