I've built one and in the process of couple more. You need to determine if you are doing a screw build or rivet build. Some say screw builds are easier but I like rivets.
If you are building on a 100% receiver your life is now that much easier. I recommend Global Trade/Armory USA (Houston, TX) 1mm receiver. Another one is Joeken's. Most people here prefer the Global Trade/Armory USA one.
Need to get your dealer or whoever to send their ink copy to GT.
www.globaltrades.com. Get the appropriate receiver (type 2) for your caliber. I recommend you have them park it for $8. Shipping is $12. Receiver $60. They give you the option of them installing a new trigger guard with selector stop for extra $22. This process takes time.
I would check out pookie's site and will answer many many questions. I learned a lot from him and how to find cheap methods. Cheap methods mean more work, lot slower but that's half the fun. For a build party you should have 20 hydraulic press, barrel press jig, rivet jig or boltcutter riveter, drill press,..... Only way to make it practical for all parties to get a shot at use.
www.pookieweb.dyndns.org:61129Next you need to demill your kit. If you have a Romy then you got some work ahead of you. You need to get the old cut receiver off from the trunnion and rear tang (rear trunnion). This will require a dremel or grinder. I grind the rivet heads flush with the receiver. I get a cobalt drill bit a little larger than the rivet and contersink it. Do not go to deep. I than get pliers and try to spread the old receiver apart while at the same time try to knock out the trunnion. Do the same to the back one. Now you got to do the same trigger guard. I messed up and cut up the selector stop. Good idea to buy an extra one. If you have a Polish underfolder should be all done. A Bugy a little work.
I going to assume you are going to do a rivet build. Now you need to remove the barrel pin. On the Romys they are known to be mega tough. Most people use a press and jig. I use a 1/4 punch that I tapered slightly. Using a 2x4 I drill out a hole so that the pin can pop out. Use penetrating oil for many days or weeks. Move the rear sight into the up position and lay on wood and pound the crap out of it. More elegant ways but this is how I do it.
Once the pin is out it's time to remove barrel. I use my cheap vise and use some aluminum angle to hold it. Place 3 pennies and pound with big hammer and my huge punch. Before the barrel comes out make witness marks so that it's easy to line up.
Now remove old rivets in the front and rear trunnion. Front ones you can punch out or carefully drill out. Rear ones will probally require drilling part of the rivets 3/4 of the way and then punch out.
I would now install the trigger guard and selector stop. I had GT install mine so I don't have any advice. I will let you know on my future builds when I do this.
Next you need to drill holes on the receiver to mate up with the trunnion. Drill with smallest bit and move up carefully checking and checking.
Once you have all the holes drilled time to rivet. I made a bolt cutter riveter. On the Global receivers they are completely hardened and you will not be able to make counter sink holes by hammering them. You will need to counter sink the holes with a drill. Just barely. See K-var's site for which holes need countersinking. I squeeze a little at a time. Sometimes the rivets can move on you so if you go slowly you can adjust. Nothing worse than having a rivet stick out after it gets squished. Once it's like that it's not moving.
Install barrel using hydraulic press or I-bar method. Install barrel pin. Check with go/ no go guage. I didn't but I wouldn't recommend it. When I test fired for the 1st time I said a prayer.
Paint or leave it.