Thanks to everyone for the feedback. The info from Southcoast Ukes and David Hurd is helpful but an answer to the original question still remains open.
I have just acquired a Mako Tenor custom built by Dennis Kato on Oahu, HI. It is a highend uke and I want to be careful not to have it explode. I will continue to try and ask Dennis directly but in the meantime I think I'll try and stay with tension totals at less than 40 lbs in my string combinations until I get the definitive answer. I am looking to experiment to get the best combo of resonance and sustain.