I GOING TO START AN OFF-ROAD PROJECT AND WONDERING SHOULD I GET A BRONCO, BLAZER, OR INTERNATIONAL SCOUT.  

Depends on what you want to do the money and how easy you want parts to be to get. In my opinion anyway.  The blazer will be cheaper on buying and getting parts and alot of the parts are out there and is easy to up grade anyway you want.  The Broncos came pretty sturdy for what the are and would not have to worry about much except what you want to modify as you go along.  The scout will be harder and the most expensive to work on but there will not be one on evey corner so you would be different.  I would go with a chevy k5 but i am partial to chevys even though i like them my boy is getting a 79 bronco and i think it is good also and has about the same sturdy running gear as my chevy. Although the scout 800 i had at one time was not fixed up (petty bad off) it was real fun.

79 bronce 351 4-speed np205 44front 9"rear 33bfg

73 k10 350 3 on tree np205 44front 12boltrear and 31s

i would have to agree, for the most part, with ronny.  i think the blazer would be your best choice if money is or is not of importance.  the 1/2 ton axles can pretty much be swapped out & have 1 ton axles bolted in.  engine & tranny bolt patterns are quite interchangeable.  & the np 205 is pretty damn strong.  and if you want to wheel something different, get yourself a first generation blazer (69-72).  the bronco has the 9 inch going for it & the 302 & 351 are pretty easy to build up.  everyone pretty much has the 66-77 broncos, so i'd probably go for the challenging to wheel & rare 78-79 fullsize bronco.  as for the scout, i would just STAY AWAY from it.  too much trouble, too much money, parts are not readily available for it at a local parts store, & everything will pretty much have to be custom built or made if you want to make it a serious wheeler.  

Blazer all the way, unless you add JEEP into the mix. Parts interchangeability from the pick-up, to Blazer, to Suburban are worth wheeling a Blazer. Engines parts from the entire GM line will work from 68-85, plus they are cheap and easy to build. Whatever you choose though, Keep it safe and Keep it WHEELIN!  

Im going to say scout. the arnt as common and wheel great!