re-seasoning outside of cast iron pan

I have old cast iron pan and it is likely silly to insist I keep the inside seasoning but it is so perfect.

Outside it is pretty clear to me that some rust is under the seasoning and I would like to take it off and start to re season that part of the pan only. I was wondering if anyone used anything other than the self cleaning oven in a house to remove some of the seasoning but not all of it.

In case yu wonder why i am so worried about the outside of the pan, its been like that for years and it bothers me not in the least while cooking, it is because when I wash the pan and put it on the stove to dry, it is clear that water is caught in those parts and it hisses as the pan heats, of course I am sure it is simply rusting more and spreading s....

ok well that was a thing which bothered me for years but after posting about it i decided that i should really do something, so i did.

I grabbed a small sharp spatula and did to the outside of the pan what i always did to the inside when something stuck, i scrapped and scrapped and scrapped the outside of that pan. Then i tore up 3 SOS pads and scrapped more and in the end i had something I could live with but far from perfect...then i re seasoned the entire pan once (if i had done the inside too i would have reseasoned 3 or 4 times).

Now the question comes up, was it worth it. Let me admit, no. I did not want to do the entire pan simply for emotional reasons. I have been using that pan since my teens and i did not want to attack it and start again. I am thinking if i can make logic prevail, i should do the whole thing from scratch. But for now, it looks really good.

Laura, I have about 30 pieces of cast iron, several from 2-3 generations ago. I've never hesitated to strip and re-season because I know I can't hurt the iron. My secret to keeping rust off is to only clean while hot so the pan will have enough heat left in it to dry fully before it cools off. I have seen the same results with boiling water, but I just find it easier to do just as I finish cooking and be done with it. I don't tend to cook as hot as some , so cracking with water isn't/hasn't been an issue. YMMV.