Invariably, the drawing you find will be the wrong valve size, and will be made out of 600 individual lines, as opposed to a polylines. Anyway, what works best for me is to convert them all to layer zero, scale it to full size if necessary, and make it into a block. Within reason, you can adjust the block scale to get a different size. IE, take a scale drawing of a 12" valve, and scale it so flange OD and laying length match a 14" valve (but overall height won't be exactly to scale). You can take drawings made for MJ ends and put a flange on the end readily enough, or put a handwheel on. Good luck. Let us know what else you find.