Ivan Vegvary wrote:

Of course I cannot drill vertical holes in the old foundation. 3" of
clearance is not enough for an angle drill or a 8" bolt.

On the first page of the google results it gives this:

http://bayarearetrofit.com/RetrofitD...g/bolting.html

Down near the bottom of that page is a section called "Bolting Homes
With Low-Clearance". Might be useful to you.

Chris