Which coilover to get?

[Jamesbb]

I have a 1950 3100 that i have installed a heidts mustang 2 crossmember along with tubular mustang 2 upper and lower control arms. I am at the point of needing to decide what to do about the coilover. I am planning on using this truck as a daily driver as long as there is no snow so i want the ride to be fairly smooth. I have been looking at the QA1 coilovers but that is where my problem comes in. I am not sure what size coilover to get and if i need them to be adjustable or not? I am planning on running a chevy 350 v8 if that helps since i keep seeing rates for springs and total front end weight. Any help with this would be appreciated since I want to make sure i order the right thing the first time.