There seems to be some confusion as to what is a type I and a Type II demil so here are pictures of both types

Also here is the general lay out of how the repair sections fit onto the stub, the left plate is not shown for clarity and the shell is not wrapped around the assembly but hopefully this will help illustrate how this "works" to make a functional receiver solution.

Below are the build and attachment sheets, these are posted to assist you in the completion of you receiver once the parts are received from HBA.

This is a new 80% "Hybrid" receiver that is a combination of Milled and Stamped components. These components are 80% complete and not finished products. To complete these products, you will need to perform some or all of the following …cut/trim shell-side plates and/or the stub from your kit, weld, drill, grind and dress welds and edges, hone the finished surfaces and/or bring materials to an appropriate state for finishing.

When completing your receiver, I highly recommend that you cut "inside" the lines, then file and test fit. (you can always take more off but its hard to put some on.

The Hybrid receiver section requires that you square up & trim the front receiver section that came with your parts kit "behind" the original locking lugs and weld the new rails in to place. This receiver is then completed by installing the Stamped receiver shell, center support and rear stock mount. (Shell, center support and rear stock mount Rivet to the side rails.)

There is no machining for F/A components done on this receiver.
The hole for mounting the stock will need threaded (Only if you are using the original stocks) and All FCG holes will need to be drilled.
Stamped receiver may need the sides trimmed to equal height so that the side rail sits flush with the inside bottom of the stamping. You will need to "Fit" rear support to side rails.

Assembly is done with (4) long AK rivets (like used for the center support or rear trunnion) and (2) short Rivets. Rivets not included.

I recommend using some small machine screws and nuts to hold the pieces together for the welding process. Some 6-32’s (or 4-40’s) and nuts will work.

Keep the screws in place during the welding and for grinding the welds afterwards…. Make sure to remember to grind out the lip that the stamped receiver slides up into.

After cleaning everything up you can remove the machine screws and install the stamped receiver. It will be a tight fit, so make sure you tap it up into the retaining lip on the side rails.

The stamped receiver should be flush with the rear of the side rails. I recommend cutting out the rough mag well opening before installing the rivets.

You should install (3) of the long rivets first. I started with the (2) for the center support, then the bottom rivet for the rear trunnion. The upper holes on the rear trunnion get short AK rivets. (If you don’t have long enough short rivets, you can cut down long rivets.

Once these rivets are in place you can then drill the front rivet hole through the receiver and the original receiver stub. Clean the hole out and then rivet with the last long rivet.

Before continuing with the assembly you will need to trim the bottom of the stamped receiver in two locations.

The mag well opening will need to be trimmed per the picture below. This is to allow the mag. to seat properly against the side rails and center support.

You will also need to trim the front of the stamped receiver for the hand guard to fit in and up against the original receiver stub.

You are now ready to drill the holes through the side of the receiver. I "highly" recommend drilling all holes from only one side (The left side) and then open up the safety hole from the right side.

You will also need to trim the top of the side rails for the bolt to be able to be inserted into the receiver.

Using the bolt as a template, place the bolt on top of the receiver approx. 1/8" in front of the inside edge of the rear trunnion. You will see that there are (2) areas that will need to be ground open for the bolt to be inserted… Mark these area’s on the top of the side rails. You can then grind these areas out with a dremel tool. They are ground flush with the inside recessed area.

Once the bolt body is installed you should coat the rails with either "liquid blue" or a sharpie. Then you can work the bolt back and forth to check for any places that may need to be filed down to eliminate any rubbing.

After completing this, assembly the complete bolt and repeat this process to check to see if there is any additional rub points.

The easiest way to hold the ejector in place is to just "dimple" the center support down (small pointed punch) after it is installed.

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