I replaced all 6 last spring but mine is a Euro car so. It sure if it’s different.
On the OEM set up the bolts are actually splined studs press for into the cat side of the flange and the nuts are on the header side.
If something has been welded it sounds like someone has carried out some sort of quick fix at some stage as opposed to doing it the right and hard way.
I had to cut, grind, air hammer and use a press to complete the job.
Few pics for ref if it helps.
Detailed thread on Porsche club ireland forum below. The IT guys have been upgrading the hosting so I guess that’s why the IP address is there and not the regular URL but google should find it in the Boxster section of Porsche Ckub Ireland Forum
http://173.249.44.54/forum/index.php?topic=8501.0
This years job is to replace the ones attaching headers to the block - fun times ahead.
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