Very good ... Depending on whether you use varnish on top or not ... in most cases varnishing is the better solution when it comes to water-resistance abrasion-resitance and UV-protection.
If you sign the print on the front you can sign into the open pores of the print (on the frame) and do the varnish afterwards or you sign onto the varnish, then you need another marker.
I sign my prints on the back ... see photo ... Everything else ask Thomas Stellwag, member here. His business in framing. He must know.