Bear in mind that a disassembled engine indicates that someone failed to repair it, and there is no telling what has been messed up. For example, the piston could have been installed backwards on the connecting rod. The right way to do this job is to read the B&S tech manual, which is available in the manuals section of this site.
The piston and rod do need to be installed the correct way around. If the piston has a notch on its top edge, the notch faces the magneto side.
If it does not have a piston notch, the correct orientation is set by the connecting rod's assembly match marks. For your engine this appears to be shown in Figure 16 on Page 288 of B&S part number 270962, Single Cylinder L-Head Tech Manual. The rod and cap "match marks" must be placed together to get the cap on the right way around. On the 130000 engine it seems those marks should be on the side of the rod which is further away from the camshaft gear. I suggest you read the manual.
Here are the rod bolt torques:
Note that the reference to "cast iron" refers to the whole cylinder casting, not the cast iron sleeve in I/C engines.