I will eventually have to install recoild, v-coil or similar thread repair inserts to fix the threads in the bolt holes for lower unit bolts. EPC tells only that it is 1" long, but is it 1/4"x20 (UNC) 1" ?
The majority of the bolts on outboards are 1/4x20 including the lower unit retaining bolts. We have no idea what engine you're speaking of or the bolts in particular. PIck up a 1/4x20 nut and screw the bolt into it... if it goes in as it should... Bingo!