Murray,
This is the same place you get on the Bradford ridge trail minus the dirt road on highway 173. I think it is exactly 2 miles to the Pacific crest trail from the Mckinley creek bridge. Turn right as you get to the P.C.T. which is also at Deep Creek and go @ another 150 yards to the hot springs.
When I lived in Arrow head I used to jog down there in less than 30 minuets. It will maybe take 1 hour to hike in. Plan on an extra 1/2 hour hiking out. The Bradford ridge is perhaps a 600 foot elevation gain coming up from the P.C.trail. That is the toughest hill the rest of the hills are small in comparison. The parking lot elevation at the bridge is the same as at Bowen ranch @ 4400ft.
Keep those good vibes flowing :~)