what to do about very high unfermentable sugar level

during my first all grain batch I mashed a few degrees to hot and I'm left with a gravity of 1.030 after 3 weeks in primary. After two weeks I added a package of dry ale yeast to see if it would get any lower, but it has remained steady at 1.030. I'm getting ready to bottle and needed advice on how much priming sugar to add. I'm worried about exploding bottles, and don't want to add to much. I was planning on adding about 3 oz of corn sugar, but with the high amount of unfermentables I'm not sure if that's too much. on the other hand if it's unfermtable sugars why would that cause them to explode?
here is my recipe...
English Special Bitter- sorta
US Pale Ale Malt 12lb 2oz 90.6 % 8.1 In Mash/Steeped
US Flaked Corn/Maize 12.15 oz 5.7 % 0.1 In Mash/Steeped
US Caramel 120L Malt 8.10 oz 3.8 % 11.5 In Mash/Steeped
Hops
UK Fuggle 4.2 % 28 g 15.1 Loose Whole Hops 90 Min From End
UK Golding 5.5 % 28 g 14.2 Loose Whole Hops 30 Min From End
UK Golding 5.5 % 28 g 9.2 Loose Whole Hops 15 Min From End

WLP001 California Ale Yeast

7:30-mashin @ 160 F.
8:00-temp. steady @ 159 F.
9:10-Collected 8 Gal. of wort @ 1.048 corrected gravity
9:50-wort boil began
10:22-add froggle hops
12:20 add 1 oz. uk golding hops
12:35 add 1 oz. uk golding hops
12:56 finished boil with 5.5 gal. @ 1.062 corrected gravity
8/13 gravity read 1.032
8/16 gravity read 1.031 added dry ale yeast to primary
8/22 gravity read 1.030

That ferment is done, bottle it with the normal amount of priming sugar.

Anything that hasn't fermented by now, won't. You're good to bottle.

thanks guys!! I went ahead and bottled with 3oz corn sugar.

How did you add 160F water to the grain and only get the temperature to drop one degree? Unless the grain was extremely hot that sounds physically impossible to me.

Next time that happens, try champagne yeast. I was reluctant to try it, but it worked on a Hefe that I mashed too high. After 3 frustrating weeks of rousing, increasing temperature, and racking onto another beer's cake, I about had it. I was pleasantly surprised to see the FG go from 1022 to 1015 in about a week after adding the champagne yeast. I just used the dry stuff.

weirdboy your right. I didn't take great notes on that first batch. I meant that it was 160 after I added the water. The water was probably in the 165-170 range before adding it. I thought it would have gone down more so I just left it at 160. My mash-tun was more efficient than I thought.
I'll have to try the champagne yeast if that happens again. I would have liked to get that down to at-least about 1.020.

If it doesnt go down, you will just end up with nice chewy sweet beer. Still beer, so dont worry!