I agree with the "split the case" guys, you have already done the majority of the work, why not spend a few more hours for the peace of mind?
Sure, chances are the bottom end is just fine. I tore my 3.2L down with 88K on the clock and the bottom end looked perfect. I COULD HAVE reused the bearings.
New mains, clean the pump and intermediate shaft assembly won't cost that much and is cheap insurance, especially since there is some question as to the motor's past history.
You don't seem to be in a hurry anyway, just take it down. You'll sleep better at night.
Ralph