Fixing misaligned rtj manifold

[scooter911]

I have a 3000 psi 5 tank manifold that has 3 inch 1500 psi rtj flanges with 1 1/8 inch studs(40 yrs old). Due to troubles with a misaligned manifold, torquing has been a problem in the past. I installed teflon coated stainless oval rings and am up to 600 ft/lbs on the studs with one flange leaking at 900 psi. I plan to obtain a torque multiplier but was wondwering if anyone had any suggestions first? Bolts were step torqued in a star pattern.

Thanks

Scoot