Scoping PTRD for long range precision shooting

[svt-40]

What do you think is the best scope mount for a PTRD?
I don't want to drill and tap receiver, do I have to?
My initial thinking was to cast aluminum mount which would house the barrel and to install a rail on it to use with regular rings and EER scope.
Or should I use the existing dovetail which the iron sight attaches to?

I heard of a gentleman who converted his PTRD to 20 mm vulcan and he devised a mount, but no pics.

 

[Missing Something]

The big thing you have to remember is the action recoils and moves back towards the shooter. So you need a long eye relief scope or your going to get bit.

If you don't want to tap the receiver I would tap out the existing rear sight and use that dovetail and have a 1913 type rail added.