Wilson doesn't want you to field strip your gun early because they feel that somehow the parts get seated properly within that first few hundred rounds. I don't know it this is a valid issue or just thought to be valid.
That being said, you can lube the barrel without taking the gun apart, so go ahead and give it some lube.
With the slide back, you can check to see that other major parts are lubed as well. I would not strip the gun to lube it UNLESS you can see that it does not have enough lube.
Field stripping a new gun is not a bad idea except that Wilson specifically tells you not to do this. Verifying things are in order, is a benefit of stripping but don't do it unless visual inspection suggests otherwise. I did visually inspect my gun when I got it and it did not need lube, so no problems.
You can also call Wilson and ask for their opinion as well or email them the query and they will get back to you in a couple days. With this being Easter weekend, however, you may not get a quick answer depending on whether they gave people days off for the holiday.