rear tow mount ideas

hello,

I have an issue with instaling a rear recovery point on my classic.

In short, the bolt heads for the standard chassis tow point (not on the cross member but underneath the car) have sheared off. The previous owner seemingly took an angle grinder to it. There is now tow bar on it currently.

So, I have spent ages trying to drill, hammer and punch the bolts out but to no avail.

So I have a new tow point to attach with no where to put it.

So I have 2 questions:

1) Any ideas on how to get the bolts out?
2) Any ideas on sturdy rear recovery options?

Thanks in advance.