Finishing the surface of props in hard to reach areas...How do you do it?

I've had my own techniques for the past years, but man I cannot tell you how frustrating it can be to have to re-work a tiny, recessed area. Lately I've found myself becoming significantly more critical of making every last piece of a prop surface (my case, a clone helmet as of late) as close to perfect as possible.

My issue is that I have giant hands, and perhaps my available tools are limited? I feel like a neanderthal trying to clean up/smooth out some of these hard to reach crevicess and recessed portions.

This could apply to application of spot putty too. I was thinking of trying to find those fine-sculpting tools and perhaps those silicone-tip ones I've seen before.

I guess I would like to know how you guys deal with it? It's easy for me to say "oh, I'll cover it with weathering" but I just can't do that anymore as my OCD is getting worse as I age