I personally would rather buy someones race bike (MX) over some Joe Smow's bike! If that bike could be bought at a decent price you could overhaul the entire motor and still be around $2000! Not too bad in my opinion
Your also older and wiser as Rocket pointed out! It's all about personal preference so ride whatever you feel comfortable with. I have always been and always will be a 2 stroke guy and took great pleasure being (at times) the only smoker on the gate!
use the old fender as a template and turn it upside down to match the faces and drill the new holes,,,,,,wholla done deal! congrats on the new bike man
if you can ride sand you can ride everything! I love the sand as well but only took a few months of crashing in it to figure it out lol. thanks for the track pics man