Opinions on what to buy to lower ET...
Solid bushings in front spring eyes?
There are cars running almost .1 faster in 60's that are the same or slightly slower et. Low 1.40's, 1.40-1.43. There's a bunch of time in that window alone. Brian's Duster went 1.43 60's with that magazine 480hp/510tq 410 stroker, a cheap shelf Hughes 10" 3500 converter (pushed through at 3200), 4.56's on about the same tire as you and around 3350#, 6.93 at 96ish.
Whether the converter is right is only something you can dicker with. It's a bit of a crapshoot. It wasn't uncommon for us to got through 4-5 converters getting it right.
I wouldn't be surprised if the car picked up .05 in 60's with a better rear set up under it.