Re: 86 prov 150
if your good just drill and tap, be aware there is nothing behind that cover for about 1/2" quit drilling if ya break through. if ya miss the 6mmx1.0mm bolt size use 1/4x 20 and resize the cover holes. helicoils are nessasary when the tap drill size for the fastener used has been exceeded.<br /> dont try to remove the exhaust cover as more broken bolts will follow.<br />with oxy/scetylene I can usually heat the cover to almost its melting point and bring the threads out with the bolt, its faster than drilling and tapping
<br /> I would not let to much shavings go down the hole, plug it with tape or a cork.
