Use the 2 kettles I say. If you are going with a grate temp...not dome temp...of say 275f then maybe your 8lb pieces will be done in 11 hours. Maybe. I'd add on 4 hours of cook time to be sure though. Can you hold it 8 hours total if it does finish in 11 hours? Probably not....but you should save as much juice as possible then if and when you have to reheat all of your pulled pork what you do is mix up some of that juice with some cider vingar and a little bbq sauce and add it to the pork. Then put it in a covered container in the oven at say 275f to reheat.
This is all just about right.....11~12 hours cooking time SHOULD get you in the ballpark, but if they're not quite there, maybe finish in the oven on site.....go ahead & FoilwrapTowelCooler anyway to hold your place....
I like a minimum of 1-1/2 to 2 hours just holding after the cook & have gone as long as 7 hours.....not recommended, but just to show how much flexibility you have.............
to be ready @ 7 AM, I'd start @ 6 ~7 PM, then there's some leeway for futzing around, if needed.....
The startup & loading to transport always seems like a time-warp to me & sometimes it's not in favor of the schedule !!!!
Two on one works fine....takes a little longer to get up to rolling temp because of the extra cold meat & you have less indirect cooking space.....if you're comfortable with two, go that way.....
See Here :
(Common for me is to do 2 on 2 kettles)
http://weberkettleclub.com/forums/grilling-bbqing/look-ma-no-therms/msg114445/#msg114445Those ones just ran where they wanted to....all on their own & ended at right about 9 hours....
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