Drivetrain 8.8 Limited Slip Differential Questions?

If by LOK, you're reffering to a Traction Lok differential, then yes....if it's designed for a 7.5" it will work, but it's not going to make the rear end any stronger. It's the smaller gear set itself that can't take the abuse, not so much the diff. You will most certainly break them with the torque of a healthy 351W in there. Had a Ranger with a 5.0 HO swap back in the day and broke two 7.5" rear ends.

...and both the 7.5" and 8.8" rear ends used 28-spline axles.

In any case....if you're going to go through the trouble of rebuilding that rear end and you know for certain you're doing that 351W swap, I'd just put the money towards a complete used 8.8" rear end assembly from a V8 car (that already came with a Traction Lok) and save yourself the aggravation. It likely isn't going to cost you any more money in the end.

And if you insist on driving it in the winter.....sand bags are your friend.