Bed wood for the 1953, 1954, 1955 and 1956 Ford F100 pickup truck is fairly easily milled if you have a few tools. All of the boards can be cut from 3/4" full oak or other hardwood. I've heard the bed wood should be 7/8" thick, but 1x material at the lumber yard is really only 3/4 inches full. Most people go with the 3/4" oak. The tools you will need are a table saw to rip the boards to correct width. A router mounted in a table does a nice job of milling the rabbets (rabbets are grooves in the edges of the wood for those of you less carpentry inclined). A belt sander is nice along with a palm sander. Good old muscle power, a flat block and some sandpaper will also get this done. Other tools just about everyone has: marking tools, squares, measuring sticks etc. You may be able to use other tools, but these do a nice job and I have them, so I use em.
Attached is a PDF that I put together showing the sizes of the bed wood and the rabbets. Some people say the bed wood should be 7/8" thick, but I used 3/4" and it all worked out nicely. I've also heard others mention slightly different measurements than what I have on this sheet. You're mostly interested in the face of the board that you see between the bed strips. If you mill the rabbets too wide you won't have enough wood face to be nice and tight when you put them all together on the bed. Like all carpentry, measure twice, cut/mill once.