Sounds like you have a plan. Lubricate the o-rings with plumbers grease and ensure they are seated in the grooves before insertion. Place a thin metal covering over the o-rings like a piece of thin aluminum over the opennings. Can't use to much grease in this case. Besides pushing the tanks apart, maybe you can also lever one elbow down while raising the other. Go slow, measure so you don't over extend, check everything prior to the final assembly, and keep your fingers from any pinch zone. Once the assebbly is in place, remove the aluminum coverings, they may be difficult to remove, hence the liberal use of grease. Before removing your blocking, start your coupling bolts. Good luck. JM2ยข...
