To mount an engine to the transom can I just use ?standard? stainless bolts from Home Depot?or do they need to be case hardened or a specific kind of stainless or what?
Standard Stainless Steel bolts with marine silicone sealant in holes and under bolt heads and washers. "Double nut" the bolts to be sure they don't vibrate loose. You'll be good to go! Good luck!