Change dpi for Ruler Guides

Question

Hello.
I'd like to use exact size in dots when making layout for my document.
Ruler Guide set to "px" displays pixel values for 72dpi, but I'll print the document in 300dpi. I'd still like to measure dots exactly, is there a way to change Ruler Guide pixels to 300dpi?
Thanks in advance.

Answer 1

Thanks for the quick replies.
What I'm trying to do is to print enlarged pixel art illustrations, which are very low resolution images that are meant to be enlarged.
The problem is, when we enlarge those low-res images, their new size must be exactly divisible by their original size. Let's say, if I have 7x7 picture (I know it's too small, just for the sake of example), it should have 14x14, 21x21 or maybe 70x70 frame, but not 22x22, since this will lead to scaling artifacts. The artifacts are only visible if you look very closely (or, alternatively, look from far away), but it appears that they are able to mess with pixel patterns slightly.
In other words, each pixel art enlarged "pixel" should ideally have the same size in real dots, or else there'll be some approximations, which are harmful to clean pixel art. Not neccesarily, but it'd be cool.
So, if it's possible, I'd like to define exactly how much points on print will the frame take in any given dpi (300 dpi is just an example).
Eugene Tyson is pretty close with what I wanted to do. But it'd be even greater to position Ruler Guides using real points in their X and Y coordinates for given dpi, not only 72 dpi (otherwise I'll have to count all those grids manually). I guess that's impossible?
Thanks.