Hi All,

I own a Ibanez RG321. Factory setup gauge of strings on it are regular light gauge (.01 to .046). I use Daddario regular light gauge. I would like to switch to a lower guage, ernie ball super slinky (9 - 42).

I am not expert on this stuff but would i mess up setup of my guitar if i go ahead with this switch. Any other possible problem i should be aware of?

If it would then can i fix/re-setup guitar on my own, especially if i do not have much experience in this area. How complicated a job can it be and should i consider doing it on my own with guidance from more experienced and expert people on this forum.

Any advice is really appreciated. Thanks!
It's a hardtail, right? If so, then the only thing you might have to look at would be the intonation, which is a straightforward job that you should be able to do yourself. But it's just as likely that it'll be just fine.
I suppose changing string gauge might warrant a check of the neck relief as well, but again, it's such a minor change I doubt you'd need to make any adjustment.
Before changing things, check your current setup to see if you have proper intonation and, if you do, how far the saddle adjustment are from the end of thier adjustment.

When going to a thinner gauge, you may need slightly longer string length to keep intonation proper.

If any adjustment is currently at the end of it's range, you might not have enough authority to get it right with a string gauge change or tuning change.

If you tune below standard,
monkey and von, thanks a lot for your replies they were very helpful!