I am having a nightmare trying to get the hex bolts out, I have tried all the usual methods for a few days but have had no luck, Is there away to remove the mushroom bit on top so i can get an impact driver on it.

Thanks

Revi

lots.lots and more lots of releasing oil,wd40 etc over space of days ,weeks then try doing it with the engine hot.If not find a kindly welder and apply the hot spanner.Bolts will often come out if you heat(expand) the surrounding metal.

go easy with the impact driver on the cast bits.....

not the answer you were looking for,but may be some help

When a pal of mine was doing this job and encountered the same problem, he deduced that access was the main issue, so he hack-sawed the mushroom bit off !!!!!!

It worked and he was then able to get in to the bolts much easier, not ideal, but it worked for him.

Cheers
Dave