As posted by chumley, Joe's GPS Track is the correct route up East Webber Crk TR 289 (not TR#248 as you note) for the ~2.8mls from the trail intersection of TR240 end / TR289 start to reach the unnamed perennial spring you mention. Here is the same GPS Route with a "brown teardrop" noted which is meant to show you the actual intersection location of 240end/289start.. http://hikearizona.com/map.php?QX=1838
. At this unnamed spring (not shown on our topo maps) is where the Tonto NF- Payson Ranger Station publishes this trail 289 ending (they actually show it to be a 3.0ml trail to the spring and not 2.8mls) even though the topo maps still show TR289 continuing further up the canyon drainage to the Rim top. I have not hiked up this trail to the spring since late 2007 and I've never been further than the spring source at ~3mls in, but
between 2006 & 2007 I hiked to this spring and back out on five different occasions and I can confirm that from this spring which is the official TR289 end, that the up hill drainage to the Rim top gets very
choked with down trees, overgrowth, and large boulders and like Joe mentions in his Oct'07 trip log- some dry waterfalls to negotiate up/down hill as well.
Past the perennial spring at 3mls in I believe that the Payson Ranger District considers this section of trail now decommissioned with no trail maintenance and I would be very surprised if there is a TH sign for TR289 at the Rim Top. Also, it sounds like you plan to backpack hike & camp. If so, just negotiating the upper 3 mile section of TR289 is going to be a challenge due to reported (see recent HAZ Webber Creek trip logs) tree downfall, some overgrowth, and some route finding required to just reach the perennial spring source 3mls in.. then the real fun begins to reach the Rim top
Do let us know how it went if you do decide to give it a go..