You need a complete 5.8 EFI motor for this swap.. oilpan to throttlebody because very few of the 5.0 parts will swap over. You also need a 28oz C6/E4OD flexplate if that's not what's on that motor now, it's not likely an AOD because that trans was never factory installed behind the 5.8. The 5.0 engine harness will plug into the 5.8 fine with one exception, in 1990 the TFI module was on the distributor and it's remote on your truck, so you'll have to either modify the existing 5.8 distributor with the pickup from your 5.0 distributor or find a later model 5.8 distributor for a remote TFI setup.

All that done this particular vintage 5.8 will be a bit of a disappointment power wise unless the stock cam is upgraded, this 5.8 motor makes more low rpm TQ than your 5.0 but less HP and you will feel that from the drivers seat, but upgrade the cam and it's no contest the 5.8 will outmuscle the 5.0 from idle to redline. This vintage 5.8 is a flat tappet motor and the recommended cam is the Crane 444232 but if that's not available you may consider converting it to a roller with the Comp 35-512-8 and linkbar roller lifters or even the stock roller cam assembly from your 5.0 with 5.8 roller pushrods.