Thanks Everyone but Please Help Again!
Thanks everyone so much for the responses.  This customer ended up just wanting a collage of four or five pictures which we made to be one large printed graphic that is like 52" x 125".  In this way, I was hoping to just install and then cut at the trailer panels, thereby achieving a seamless install.  However, I have a new dillema...This is not a rectangle but basically connected staggered photos.  I am trying to install without premask using IJ180CV3 with 8518 overlam, properly outgassed. Should I be using premask?  It is a flat trailer with panels and pan head bolts, not rivets.  I am having one hell of a time working with the graphic and have destroyed one already.  I am hinging using a horizontal center hinge.  The vinyl seems to be too flimsy and I keep overstretching or getting crows feet.  Please help folks, stressing out on this one...too expensive of a print to have to do over.  Thanks for your time everyone!