Makes the 1-2 stupid firm when used with a shift kit, so you have to counter it with less fluid flow in the VB (the feed holes being drilled) and use the softer valve train accumulator.
Pin maybe if you have too much clearance.
Hindsight, like others, is don't bother. The "Vette" servo has plenty of apply force and is certainly not the weak issue with 60Es... that's the 3-4 pack, steel input shaft into an alu drum, the sprag, etc.
LASTLY, remember downshifts are what the 60E just doesn't like.
I agree with Silveradodude74. Just get the $15 Vette servo and use your stock pin. I had the billet servo installed and a month later was rebuilding my trans. The Vette srvo is a great mod for a truck, even better when joined by a shift kit.
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