Enable Lightbox on Random Images block

Since I've been unable to get any sort of response on some major issues regarding fixed-width layouts, image nodes, and lightbox, I've given up hope on making the image nodes visible to the public and have instead altered gallery pages to launch lightboxes directly. However, the last issue remaining is the "Random Images" block provided by the image module; it links to the image node, not a lightbox full size image.

Is it possible to force the thumbnails that display in the Random Image block to link to the file directly, so a lightbox is displayed? I looked at the link function in the image module, but I can't make heads or tails of how to force a custom link onto it that points directly to the image and has rel="lightbox" in it.

I do hope that somebody can help, I am at my wits end trying to use lightbox throughout my site consistently. It is a beautiful module,but it's very hard to make it work everywhere one would want it to (referring to the links on the image node, which caused me to have to go this alternate route in the first place).

Please, help me get this resolved, anyone!