Taking off second Cats. for delete bypass.

[eomak]

Hi,own a 03 boxster and iam getting those fab.speed secondary delete. pipes. I had the car up on jacks and was looking at secondary cats and the way they are bolted on and setup. It looks easy enough to take out on my own,but i notice the connection from the first cats. to the pipe to the second cats. the 3 bolts that connect it to secondary cats.The top bolt seems to have a nicely weld spot on the nut.As to me looks to make sure it doesnt come lose.This normal?I havnet tried losing it jsut want to know if that is factory done. If it isnt any reason y that top bolt would be welded? Thanks.