75 Duster Tetnus Shot and band aids

If the engine was original to the car I would see if the block could be saved. I got lucky today AMD still has fenders so I ordered up a right front fender. I won't have to mess with that rusty right side one now. Looks like metal also got into the main bearings. The number 3 and 4 main bearings got tore up a little bit. Number 3 cap bearing just outside of the oil groove is messed up and the number 4 main cap bearing has been damaged also. Just got the crank out found slivers of metal on the main bearings on the engine side. I'm thinking this metal and damage came from the poor welds that someone did inside the oil pan. When the welds broke the little pieces were sucked up in the oil pump and caused the damage I found. The carbon and the issues in the cylinder walls are separate issues from the other damage. What are your opinions?