I think with a bonded title, the previous titled owner's only compensation is the money behind the bond you bought. Your liability is that if the insurance company pays off on the bond, they will then want that money back from you.
So there's no need to not work on the truck for fear of a past owner appearing. You can also legally sell the truck with as a titled vehicle as well.
I did a bonded Texas title on a Chevelle I used to have so I'm not making this stuff up.
I've been told a mechanics lien is the quicker, easier, and cheaper solution BTW. I guess you have to have or know someone with a shop I guess.