Hi Darren; I had a look at your longerons in the picture. It was a little hard to tell but it does not look like they were split (I might be wrong). If they are only surface cracks that do not run through the longeron then don't forget that you will be adding a longeron doubler down both sides that will tend to hold the proper shape and also strengthen the top.
Can you post a better picture? Regards Myron (Dan) Freeman Indpls, Ind. 46203 USA. Home of the 2007 World Champion Indpls, Colt's mfreem...@indy.rr.com