S31,
You can do a very credible alignment and probably better than you can get on a high buck machine with simple tools. It takes a lot of figuring and careful measurement but then you really know what you have. (from a parctical perspective set the toe as close to zero within the specs, that gives the best tire wear)
Toe
The method Protrash mentioned can be very exact if you mark the edges of the tread you are measuring to then measure with a good tape measure, with the marks forward then roll the truck and measure with the marks toward the rear, then you can calculate the toe and set it to any value you want within 1/32" if you are careful. Double check that the numbers are repeatable.
Camber
A little electronic angle tool (they use them to set the angles on saw blades, good to 0.1 degrees) about $30 from Harbor Freight. You can use that to set the camber using a steel bar that locates on the rim flanges. (great tool for setting drive shaft operating angles too)
Caster
Caster setting requires ball plates so you can rotate the steering without distorting the suspension. There are a lot of ways to trick that including greased steel plates, greased floor tiles (grease between two plates or two tiles) ... etc. Then use the angle measuring tool to measure camber change with steering angle. It gets complicated but you can calculate good numbers with this method. This link gives the formulas.
http://www.hunter.com/pub/undercar/2573T/index.htm
Remember to always roll the truck to a stop before a measure so the suspension is in a realistic state.
I have a friend that uses simple tools like this to check the calibration of multi thousand $ machines, as a professional suspension problem solver.
Good luck,
TR