You will need to get the timing chain cover for an older 302.
Also needed will be the shorter roller pin for the cam and the two piece eccentric roller. ==Warning== taking out that dowel pin on the cam is not going to be easy. Either you may have to use vise grips or cut it.
Can't say for sure how well this will work as the 5.0 HO may have different bolt mount holes etc.
Approach this conversion with caution.