truck wont start

You may want to check the main fuses in your relay center under the hood, generally these are rated @ 40, 50, & 60 amps and about an inch and a quarter wide, . If one is blown it could prevent completion of your ignition circuit, however what caused the fuse to fail must be considered. Did you disconnect the battery before changing this wire ? If not , that may have caused a power surge to your computer monitoring system, thereby causing other issues.

Also aluminum wire is a poor choice for use in 12 volt systems, as it will not handle the current draw as well as copper wiring will. I would use the same gauge and type of wire as was removed.