My engine builder's shop was next door to a tranny place. In addition, the tranny guy used to race a '68 FB RA II and a GTO so he was pretty familar with Pontiacs. The two of them got together to determine what new converter would be good for my combo:
490 HP 455 (punched to 462), E-heads and intake, roller cam, Doug's headers, 2.5 inch Pypes exhaust, TH 400 tranny, 3.55 posi rear.
The answer was a custom made 2800 stall converter. I agree that 2800 is too high for your combo.
2012 Mustang Boss 302 #1918, Competition Orange. FGF replacement 2006 Mustang V6 Pony, Vista Blue. Factory ordered. 2019 BMW X3 (Titled to the wife, but I'm always driving it for her. So I'm claiming it) Old projects, gone but not forgotten: 1967 FB 400, original CA car. After 22 years of work, trashed by the guy who was supposed to paint it. I had to sell it. 1980 Turbo Trans Am 1970 Mustang fastback, 351C 4Bbl, auto 1988 Mustang GT, 5 speed 1983 F-150 4x4, built 302 1994 Chevy K2500 HD 4x4, 454 TBI