They probably said change the motor mount to a stiffer one so the flex pipe doesn't rub against the firewall when the engine rocks/moves. I don't think that was a issue with this header but I'm not 100%. You should be ok.
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they reccomend replacing the motor mounts because it has a ball joint where the downpipe connects to the actually header i reccomend getting another brand header because with the movement it will cause the exhaust to twist and hang really low.
made my exhaust move and not line up at all with the cut out in my rear lip, but that was an easy fix...... when it comes tot he install it wasnt that hard, the header bolts came off for me pretty easy but fitment was an issue as it was a good 2 inches short to reach my exhaust which was not stock at the time.... as for the mounts, I still have my stock ones in and have not noticed anything and dont see there being a problem as it is no where close to comeing in contact with anything.
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