I have unfortunately rubbed off my marks on the injector wires. Is there a way to determine for sure which injector wire goes to which injector?

Are there any factory marks or numbers on the wires or plugs? Are all the wires a different color? Look at a wiring diagram for your vehicle and see if there are any pin numbers designating what wires go where.
A wiring diagram maybe available at autozone.com in their free repair guide section.
For future reference please identify your vehicle with the model year and engine. It will make it easier for someone to give you detailed help.

good luck pal

Yeah, I got it. Sorry, I'm working on my '94 4x4 pickup w/22re. Anyway, the wires are different lengths. The shortest goes to piston one and the longest one goes to piston four. Thanks for your reply.heres my project.
http://myspace-735.vo.llnwd.net/00576/53/72/576152735_m.jpg

http://myspace-684.vo.llnwd.net/00505/48/66/505636684_m.jpg