I am doing a frame up on my '50 alone. I only work the weekends when I do not have other things to do. I am at about two years. Mechanicals are just about done. Engine, tranny, rearend, brakes, suspension, steering box and frame done. All patch panels in. Most body work done, in primer. Have to do finish body work, install 3 point belts, paint and electical. Hoping to be done by July 4th this year. (Two years since it was crunched by a hit and run driver. I have owned it for 29 years.) I am no pro, but not a rookie. Having good tools helps (e.g. compressor, air tools, etc.)
The absolute biggest factor in getting it done is you. How much do you really want this? Right now it seems like a fun and exiciting project. After a year or so of being in the garage, contemplating another day of the blast cabinet, and your loved ones have pretty much given up on you, it may not seem so fun. Check the local classified ads for items like, "59 Chev Truck, project, most work done, extra parts" and you will get the picture.
I think you would find that most folks here with fully restored trucks have a unique perspective on their vehicles. I know that when my truck was hit, I went through a grieving process that kinda surprized me. I still am somewhat embarrassed to admit this, but it showed how much I care about this old truck. I don't dread those long days in the garage, I look forward to them.
To answer your question on how long it would take, like most things old truck..."that depends on a lot." But remember a old adage, "Figure your projected time and expenses, then triple it, you will be somewhere in the ballpark." Good luck,
Steve O