HELP: The muffler bolts backed out of my Briggs and Stratton 49T877

[heavy_kevie]

Have a 49T877 engine and the muffler bolts backed out. Does anyone know the correct bolt torque? According to an engineering website it can be 80 in lb into aluminum and 192 in lb into steel. The only thing I have found so far is this but it is saying 150 in lb the bolts are 5/16-18.