On my sub I used 2)2 ton moter hoist ,cut the head off and razed it up about 8",boated to the fire wall about 8"down from top bend,drilled 3/8"holes grade 8 bolts ,with fender washers,I left them in for ground hook up post,,in the back it was cut off after the 2 seats,used 6"c-chanel,bolted to where the back of the seat hooks to,but the sub was cut off after that,,used 1" ratchet staps to hold it in place from rotation hope this help