shouldn't be too difficult if it's an original manufactures style sending unit. some are threaded directlty onto the thermostat housing and has an easy to plug in electrical lead coming from the undehood wiring harness that goes to it. it's possible that your yearmodel and engine make could have the type that is located on the lower side of the block/water jacket...it is also an electrical type sending unit. BUT if you have one of the older BUICK GS grand national turbos, well then, it would be a good idea to invest in one of the small owners automotive manuals put out by CHILTON. they can be purchased at most auto parts stores....at least, here in texas, they can. they,re comprehensive and a ''MUST HAVE" for anyone who is serious about their personal toy. i'm old school and was raised in a family of GM enthusiasts.