Although the Sequoia is based on the Tundra, there are probably differences underneath. Why not buy a system DESIGNED for a Sequoia?
If you're doing it for performance, don't bother. This mod alone will not provide much increase on the under powered '01.
I put a turbo muffler on my '01 Tundra and it sounded real good, but it was no faster. It only SOUNDED faster.
My friend spent a bundle on a complete dual system and his truck was no faster than mine.
P.S/ I finally decided to get a new Tundra with the 350 V8 and it has TONS of power right out of the box.