Mike P.
The 982 is indeed a very nice piece of iron, the twin cylinder Onan is a good engine, though very expensive to repair or replace, and the pretty much bulletproof IH drivetrain makes it an excellent tractor. I'm not sure if the 982 has internal or external brakes, my 129 has external brakes but a 1650 I recently parted had internal brakes, so you'll have to look. You'll need a tractor with external disc brakes to even think about doing dual pedals.
Other than the brake issue, the front hydraulic ports can be added with fairly little trouble, but you'll have to fabricate hoses and brackets, and probably convert the current lift lever to a dual setup. All of this can be done, but you'll still have a lot of fab work on your hands.
My thinking is that a 149 might be a better choice. A good 982 still commands a hefty price, and all that nice streamlined cowling around it will make the fab work more difficult. It will already have the ported hydraulics, disk brakes, and not an excessive amount of cowling to get in the way. They are also a lot more available than the 982s at a reasonable price, and the Kohlers are cheaper to overhaul and repair than the Onan, as long as the block isn't completely worn out or ventilated. The single cylinder Kohler will shake more than the Onan twin, the effect will be more like putting a Honda Gold Wing up against a Harley Davidson Fat Boy. The Honda runs smooth as silk, the Harley will shake rattle and roll.
In the end, its up to you.