I used the exact bolt locations in your picture.
I put mine in with the valve cover off.Here is a picture of my 261 on the hoist.
261 on hoist 261 on hoist pic#2 I did use a load leveler that I purchased from harbor freight.
Make sure you use strong bolts and make sure the bolt head can't slip through the chain link.Just get in there and do it,you'll be fine.
Tim