I would leave that log in tact and find a nice shady spots and an Oak w/ some mushrooms. Rub the shrooms on the Pecan log and place in the shady spot. If you can, cover it with leaves. Let it site for 6 months to a year and let that bad boy spalt. Pecan is fairly unassuming wood as a pen goes but spalted pecan looks great. When your ready, now or then, and if your up for a drive you can come on up here (Spring area) and we can break it down on my bandsaw and I have a Chinsaw too if that is needed.
Edit:
As for cutting it, like others have said, X-Cut will give more character, IMO, than straight grain but is prone to blow outs so your tools must be true. If your intention is to cut the entire log into blanks I would do Straight, X-Cut & Bias (angle) cuts since you have plenty to go around.