For low-speed trail stuff (and not long-term like fieroboy_gt did), is it safe to leave my hubs locked and drive in 2wd?  And shift between 2hi and 4hi without getting out to lock/unlock hubs every time?

Yes.

Thanks guys.  I was thinking about it, if anything, it locks the two front wheels to their respective axleshafts...but not together since it is still an open diff.  Everything is still spinning freely, not "locked up".  So minor 2hi driving with hubs locked seems like it's non-damaging as long as there is good upkeep on the car.  Besides, by the time I get back to the pavement to drive home, I can unlock them and go on my way.  The manual hubs will be better for me since I will be flat towing the Tracker too.
Sorry for the thread hijack, but while we were on the topic...

That's why people like twin sticks & 2WD low... so they can keep the hubs locked, but just go from 2WD to 4WD from the cab.

That's why people like twin sticks & 2WD low... so they can keep the hubs locked, but just go from 2WD to 4WD from the cab.

That's what I've been investigating for awhile now.  Stan (37Kicker) makes a neat twin stick but I decided against it...for now 
Cause I might as well do the 4.24 kit too since I'll have the case open...and for right now I'm just trying to build it to "basics" to see how well it does.  I might be just fine with 2hi and 1.82:1 stock and open diffs...but I haven't even driven it yet!!!