I'm trying to do something similar with a (badly) sporterised No4Mk2. Bubba drilled and tapped crooked holes for a Weaver T01 scope base as well as cutting the barrel, so this one was never a candidate for restoration.
The appearance I am going for is Enfield Enforcer, though. I have a commercial target buttstock - monte carlo and full pistol grip, and I've cut back a rear handguard to match the length of the sportered forestock, but there is a some work to do there to fit the stock band, because the stock would have tapered to a smaller diameter for a No.4 stock band. I intend to leave it .303, so I'm not sure yet whether I will re-barrel it of have it cut back a bit further and crowned and fit a target (hooded) foresight. To begin with, I intend to use one of my Cad-Technik mounts for the scope to see how much potential it has before deciding whether to try to fill the holes from the T01 and re-tap for another mount.
Angel's rifle looks good BadgerDog, which is encouraging for me. Thanks.