Hey, Ralph;
This is, at most, a 3-4 hr job at a service shop like Alcan, IMO. I changed my springs "solo" - it took a full day. However, when I changed my axles out at Hohenwald last year, "DeeBo" and I started around 8:30am and we were at lunch by noon that day. I'm sure Lew and his team at Alcan would have the springs done in less time.
Plan on getting there the day prior to your appointment and you'll be on the road by early afternoon.
Good luck!