Mk1 G60 rebuild or Replace

Had this running absolutely great until charger blew,metal bits sucked into engine damaging valves and bores..
Had a rebore to accomadate wossner 82.5mm Pistons, replaced charger, ran bad from the word go, misfire, plugs black.. Now charger sounds very rattly, metal noise😦
Checked bores again, scored, Pistons look pitted and melted, constant misfire..😪

Thoughts on either rebuild or go for 1.8 20vt ??
Not very confident on a g60 at the moment