To put cross over steering on my truck, what year is best to get an ifs box from for my '84 P/U?

If I go to a bone yard is there anything I should keep an eye out for on the boxes?

Any certain years have problems to steer clear from... <img src="/forums/images/graemlins/lol.gif" alt="" />, haha, get it, steer clear, okay, enough jokes <img src="/forums/images/graemlins/notooth.gif" alt="" />

When I find one are there any other components i'll need along with it, for example the lines?

Thanks

'84 PU low & slow
Central Valley Crawlers