Welcome to jeeps.com. If you have already obtained the replacement parts , there should be a gasket , screws and a spring. It's been some time since I replaced one for my dad on a '91 s-10 4.3. The procedure will be the same. It's best to remove the throttle body since you may need to clamp the regulator housing down to control the spring since there is a bit of pressure that is a little difficult to control while trying to thread the screws back in . You will want to be careful on this step since you don't want to strip the threads while starting the screws in. With the throttle body off , you can get a C clamp to hold the regulator body down and easily thread the screws . But if you decide to change it in place to avoid upsetting the manifold to TB gasket , get someone to press down on the regulator housing while you thread the screws back on. Don't rely on turning the screws down to compress the spring while starting the screws , the aluminum is a bit soft and you risk damage to threads . You may even be able to devise a way to anchor a small pry bar to hold the regulator body down of working alone . Just be sure you devise a good anchor point . No injuries please. You may be able to fab something from the air cleaner attaching point where the screw(s) thread of you feel they will be strong enough. Did this before on a model 300 Tbi for a GM 4 banger. If unsure or hesitant to proceed , please post pictures and will try to assist. Be certain to get the right repair kit for your throttle body.