You could of course try removing them "by the book" [:D]
it really works ................ sometimes if you're lucky ...
In this case one stud really could be removed with a screwdriver.
Three only needed two nuts locked together and a normal spanner.
Last one put up a small fight, but after an extra hour of soaking with penetrating oil and regular (light) taps with a hamer, it also surrendered.
But the studs had been soaked in penetrating oil for nearly a week before starting on them.
Also left the bolts in place to avoid extra tension/friction on the studs.
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<font color="blue"><i>1981 TR7 FHC Sprint (better known as 't Kreng)
1981 TR7 DHC (not very well known yet, but back on the road)
Also a 1980 TR7 DHC, 1980 TR7 DHC FI, 1981 TR7 FHC
http://tr7beans.blogspot.com/</i></font id="blue"></center>