I haven't done it, but I think that is one of the more popular PMA routes. I've found this site to be very helpful with PMAs - http://bwcawild.com/

I'll work on getting that route working on the maps. I've worked on it before, but I've never had quite enough information to complete it. I need the locations of portages and generally how much longer the route would take than a typical route.

The first half of June should have higher water levels, but it isn't guaranteed.

Because it is a PMA, the portages are not maintained. The river/creek is choked with beaver dams. I would think that if you made it from Beartrap to Iron in one day, it would be a really, really long one. I think I read somewhere that the last portage into Iron is really tough. I would get a PMA permit and plan to camp on Sunday Lake.