Smartest way to do plugs, o-rings, tubes and coils?

[yimmy149]

I'd like to replace the plugs on my car soon, and it seems like that would also be the best time to replace the o-rings and any cracked spark plug tubes and coil packs.

I'd like to minimize the amount of down time on the car waiting for shipments from Sunset, and at the same time not waste a bunch of money on parts I don't need.

I was thinking I'd order all 6 plugs and 6 pairs of o-rings, but only 3 tubes and 3 coil packs. Then do one side of the car, if I end up using all the tubes and coil packs, then order more before starting on the other. Is that a good plan? If I end up with left over parts, can I return them to my local dealer?

-james