Mine is now a 4-speed, but I had an easier job as it was originally a 3-speed. It's not really too big of a job if all the pieces are available (and they are on eBay quite regularly). I really wanted to convert mine to a 5-speed, but I was unwilling to jump in for the extra $$$. At the time, I figured a 5-speed was going to cost me around $3.5K. As it turned out I spent quite a bit more than originally planned because the 4-speed jumped out of gear on acceleration or deceleration. So I had it professionally rebuilt. Anyway..... all this to say that as with many of our projects, there are hazards, so beware.

Modern Drivelines in Idaho markets everything to do the 5-speed conversion, including clutch cable actuation.

All that said and done, I would be 1st in line to help you either way you decide to go. Just let me know when.