The person I purchased this from was in the process of putting the body on a 1990 S10 PU (he only has the S10 stripped down except removing the cab). The Chevy 3100 appears to be completely original (haven't got it home yet to really check). He claims that once the conversion is complete and a few items fixed (bench seat, etc) it will be worth about $30,000. I'm not looking to get the Chevy 3100 back into perfect original condition because I want to be able to drive it some.
What is everyone's opinion, keep it stock or do the modification?
The fact is that a couple of us here on the site, maybe more, have been using these as daily drivers. I have over 115,000 miles in 22 years driving my '49. I did change the torque tube to the '57 3.90 rear and added a 3sp+overdrive but it was easy and easily reversible to stock. Many here have just changed out the differential to the 3.55 kit and have many carefree miles.
Good luck with your decisions. BTW, IMHO, there is NO WAY, "... once the conversion is complete and a few items fixed (bench seat, etc) it will be worth about $30,000." NO CHANCE, unless you are prepared to put extreme money into the truck, even if you did all the work yourself. Again, I represent one opinion.