If your trans is only noisy in 4th gear I would very carefully inspect the 4th gear and the cluster gear. 4th is the one that is attatched to the input shaft so that would make sense why it sounds like it's from the front of the trans.
Your pilot bushing may be bad but its doubtful that's where your noise is from.
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1967 GTO, 432 (428+.030), 4-bolt mains, factory Nodular crank, scat rods, icon dished pistons, Lunati HR 243/ [email protected], .618/.622 lift, Edelbrock 72cc round port heads, 10.5:1, offy 2-4 intake, Edelbrock 650cfm carbs, Super T10 trans (2.64 first), BOP 10 bolt w/ Eaton posi and 3.36 gears
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