You have 2 routes you can go. Unless you know the sausages have been cured, I'd hot smoke them. 225 until you reach 155 is good. The best setup for that is minion method. I think your sausages will turn out fine this way. If they are cured sausages you can do a medium heat smoke and get a lot more smoke flavor on them. This is cooking for 2 hours at 130 then going up to 160 until an internal temp of 152 to 155 is reached.
There is the 40 to 140 in 4 hours rule. Its most important for uncured sausages because you run the risk of botulism if you cook them any slower.
Personally, I think if you cook them at 225 in the WSM they'll turn out fantastic.