Several options available. The OEM kits are very good for street\strip use although the rubber looks deteriorated from the outside the 40 year old rubber is still good on the inside, and modern OEM replacements have improved formulations. The MOOG improved is more firm than the original rubber and probably the best compromise. The Urethane (polly by Golly stuff) stffens the suspension system dramatically, increases noise, vibration, harshness, and sets up resonances in the chassis at certian speeds. The lower control bushings are very difficult to seat properly and an cause alignment problems. If the car is driven frequently MOOG improved is the first choice.