720 LP Fly wheel,LBS. of torque on bolts

Ben, that's a tough call. Depends on if the bolts are dry or lubed, the amount & type of lube on them. They are easy to over-torque & once over-torqued won't retain the applied torque. The basic spec would probably be around 200' lbs lubed & maybe as high as 270' lbs or so dry, assuming clean threads & non stretched threads in both cases.
~Look your bolts over VERY carefully [see picture], there is a chance they may have been over-torqued at one time in their life & if so they must be replaced. As a good rule to live by, it is a good idea to always replace those bolts if you don't know the tightening history of the bolts. ~I usually install grade 8_ 3/4 X10_ conventional bolts with a light coat of oil on the threads & use a 2' cheater bar on the socket & give them a good snugging up. Those bolts will easily go to 300' lbs dry but I keep them under that so the flywheel isn't damaged [ probably around 275' lbs or so]..... .....