If you can get to a 15lbs base weight you will be doing fine. Beyond this the key to managing you pack weight is being able to plan your resupplies. Since is drive in from Phoenix, I pass through Tuolumne on route to the valley. When I hiked the JMT I left a resupply in a bear box at one of the parking areas and picked it up on day 2 of my hike.

If that doesn't work, you can mail resupply to the post office at Tuolumne. The next resupply is the store at Reds Meadow.

Using Tuolumne and Reds Meadow you can keep your food load to 2-3 days for the first part of your hike. Then you have VVR and/or MTR, 2-5 days after Reds Meadow (depending how fast you hike).

After MTR you'll be looking to resupply in LeConte Canyon and/or near the Kearsarge Pass trail junction. Packer outfits make regular trips to these locations and you can often add your stuff to an already planned trip (and keep costs somewhat contained).

If not, Parchers will hold a resupply (exit a LeConte Canyon to South Lake) for a nominal fee, and you can arrange similar at Onion Valley.