I rarely have time to get to this site but because a Brute conversion is something I've drooled over, I wanted to check out this thread. Here are my thoughts:
-From a practical standpoint (yes, even Jeep owners can be practical sometimes) the longer wheelbase can improve function. A slightly longer wheelbase helps with stability when climbing obstacles and doing some off camber maneuvers. It will handle better on the road and ride better overall. There is a slight downside if you do really tight wooded trails where a short wheelbase comes in very handy.
-I disagree with those suggesting to start with a beater. You will be investing $10k+ to do the conversion. Do you want to put that into a piece of junk? If you start with an older, high mileage, well worn Jeep that $10k will easily double. Once done you will want to do the rest of the bodywork so it looks good, instead of just a long wheelbase beater. Then you have a nice looking Jeep on the outside- need to do the interior to fix the worn seats ,beat up dash, etc. Of course that worn out engine will have to go, and better go through the brakes, axle seals, bearings, etc. Of course after all that you need some cool accessories, so add in bumpers, winch, tires, lift... You already have all that. If you really want a Brute conversion, do it to a nice Jeep you already know the history of.