Dave, I hear you man, but I've rang a lot of toyota people over the last few days and they're all telling me they don't have any. ARP apparently don't make the aftermarket 4AGE items that fit K motors anymore.
I thought was all a bit odd, but if anyone knows where to get some of the damn things please let me know.
I'll do some calculations on these based on the torque setting, that will give me a good idea if the high tensiles are up to the task.
As for the Auto/Manual loading, I don't have evidence, that call is based on simple deduction. Manuals will have some axial bolt loading via the clutch springs being engaged/disengaged, while autos don't. The manual can also see greater shear loading if the driver is a brute (ie clutch dropping)
As for the bolts being fatigued I greatly doubt that, they haven't snapped, and a fatigue failure with that sort of deformation should snap fairly quickly.
I had another look at the flywheel assembly after Trevs comments, I agree that they are not the correct bolts. I don't know what the standard length is, but these don't have a straight shank because they are only 15mm bolts, the flexplate is quite thin. As for whether these are high tensile or not, I'm hedging my bets with no.
I'll do some numbers and see what I come up with. If anyone knows where I can get OEM bolts though, please let me know!