Just a couple of tips, depending on which system you have (open or closed), but actually pretty universal.
If the piping goes down then up (any kind of air trap), you have to have some way to let the air out near the highest point on the engine end. If you have a radiator cap, it has to be near the stock height or above the engine(below doesn't work well). The air outlet for the engine end should be close to the same level as the top of the radiator cap (I used the heater in hose and cut in a "T" with a screw cap). And the recovery bottle should be pretty close to the same height in relation to the raditor cap as it was, you can go a little higher with the radiator and cap, but move the recovery bottle along with it (it just seems to work better that way). Though the recovery bottle location isn't as critical. A little thought can help avoid problems (water/coolant flows down and finds it's own level).
You almost have to have two openings, if the pipe goes down then up, because the air won't do it on it's own, quickly or efficeintly. And if the two openings aren't at the highest (or near) point in the system, your coolant is gonna run all over the place (it's gonna find it's own level). The last bed mount I did for a PU required a little tweaking. I lost a quart or so of coolant everytime I opened the bleeder cap, I lowered the radiator a little and everything was fine). I probably could have raised the bleeder outlet.
Also found out, you have to periodically bleed the air out of the engine end (I don't know where it comes from, but it seems to grow).
I also used blank heating pipe, a little heavy, but pretty much bullet proof. With some sand and a torch you can put some fairly clean bends in it. Heating galvinized pipe (enough to bend it) releases a lot of poisonus gas.