On the 3:55 conversionm are you talking about rearend gear ratio?If so that sounds like a good combination.I would definitly go with a dual master cyl.power if possible.I see so many guys fix these old vehicles up to go fast,and do nothing with the brakes.On my 55 I have a dual power setup with GM discs on the front,brakes work great.On my 65 which has a 500 Cu.In.caddy engine I have a dual Master cyl.with discs on the front but not power.This setup works good tooI went the easy route on the 55 and bought a Power master cyl. from Chevy Duty,that mounts right under the floor in the original position.

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