Say someone bought a new alternator, but that new alternator had a larger pulley than the original.
Could said DIYer just go buy a larger belt?
Or would that be of some kind of detriment to one's engine components or the alternator itself?

TL;DR: Is it necessary to keep your original alternator pulley size when getting a new alternator?

if you had an impact wrench it would be easier to swap pulleys (most parts stores swap pulleys once in a while). but if you had a bigger pulley and used a little longer belt you should be fine. your alternator will spin a little slower but unless you're running lots of extra electrical stuff it won't matter. -- I looked into pulley kits on my mustang a few years ago and slower alternator was an acceptable side effect for that 1/4 hp....

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2011 4.0 4x4
265/75/16 BFG all terrain
flowmaster delta40 side exit
T-bars turned, load levelers & add-a-leaf and a hula-monkey on the dashboard

I appreciate the reply
It's a more powerful alternator than the original and I'm only running my basic power options (windows, locks, ac, aftermarket stereo but no subs), so from what you're saying I should be fine.
If I remember the year correctly, I believe I've got an 06 (or 04 or 08, but leaning toward 06) Mustang engine in my ranger. The original owner swapped it out when the head gasket blew. Still the same size though, 4L V8.