AK to AR Adaptor

I need to fabricate an adapter for a Valmet Petra prototype to attach an AR buffer tube and pistol grip. I want it to be fabricated out of ordnance steel. I prefer 4150, but 4140 would do in a pinch. The adapter is to be secured in the receiver using the existing threaded hole in its back, and a transverse pin fitted in the existing channel across the receiver slot aft of the trigger bar. The buffer tube interface is to include an engagement tab for an M4-style receiver plate, in order to align the buttstock and buffer tube coaxially with the barrel. The pistol grip adapter should be of the standard AR type, suitable for fitting a Hammerhead grip in a CA DOJ featureless configuration. The finish should approximate the quality of the glossy Valmet receiver polish, with a nil clearance in the receiver slot, for no wobble of the stock.

I would be very grateful for any advice or referral in this matter.

Attachment 43824