The 180 gr. bullet from your .358 just makes the .358 into a ballistically inferior .308 so not sure why you would bother with the rebore is shooting such a light bullet?
IMHO the good .358 bullets start at 200 grains and up, 225 is a good compromise of power and penetration, 250's are deadly on big stuff if not too far away. Crashman suggested two of the best.
Case capacity is limited, so dense ball powder like Win 748 is a good bet, that's what I've used.