Here are the original parts I kept as spares from my original Minicraft/Hasegawa 1980’s build. I also found parts from a 1980’s build of the Revell kit #4437 which was finish in USAF Grey. I actually just used the Original M/H stabilizers on the recent RNLAF build, as the kit I used did not have the original small stabs.

2 attached images. Click to enlarge.

Welcome aboard George. Looking forward to this!

I was wondering if the Italeri kit was the kit to use and thought of other alternatives and what was the objective of this build. I figured I should build the actual kit from the '80s, but I was missing parts from the Hasegawa kit. 🙁
Just a week or two ago, I came upon the Academy kit #12444, which turns out to be a 'copy' of the original Hasegawa kit!

6 attached images. Click to enlarge.

That is a nice set of decals for an offordable amount of money, George @georgeswork

Thanks John (@johnb) and Erik (@airbum)
The Danish Flag is definitely there Erik, it was on the 2nd prototype aircraft #01568 – I read somewhere that last flag is Iran - original considered to be a buyer during the Shah regime.

Here are some photos of a little progress on these basic kits
I happened to find another Academy kit # 12444 for the cheap price of $5. It was then that I thought of having the extra decals and since the Academy kit copies the Hasegawa close enough, maybe I can use some of the parts from the extra Academy kit to fill in the missing parts and complete the Hasegawa model. I would need to use the jet intake and the nose from the Academy kit and I will need to use the original Red/White/Blue Rudder Tail from the original ‘80s Hasegawa build. Therefore, it looks like I am going to have 2 prototypes. Maybe both Red/White/Blue or maybe one build of the camouflaged prototype – I don’t know.
I found the original cockpit from the OLD Revel kit (#H-222 I believe) in my spare parts box and wanted to use it for the Hasegawa prototype. I had to add the joystick, repainted the seat, and added some masking tape seat belts. It was a perfect fit in the Hasegawa fuselage.
I also found a Hasegawa cockpit tub and seat from a recent build in the spare parts box. I added the tape belts and had to shave it down a bit to fit inside the Academy fuselage.
When I started gluing, you can see the Hasegawa kit just fits together a little tighter than the Academy kit. I added the nose section to each build, I’ll need to do some sanding and filling on both build. The Hasegawa front pitot tube looks much finer than the Academy but it just did not fit, so both builds get Academy noses.
Next was fitting the air intakes together – both will be Academy. The Academy intakes fit quite nicely onto the Hasegawa fuselage but some filler may be required when I get there. First I decided the carve out the shallow intake scoops to add some depth. Definitely looks better.

9 attached images. Click to enlarge.

You're making some real good progress, George @georgeswork
Would love to see another Falcon added.

Thanks again Thanks John (@johnb) and Erik (@airbum).

Did a bit of sanding and putty work. things are moving along.

Did a dry fit on the intakes onto the lower fuselage.

The Academy scoop intake on the Hasegawa fuselage fits ok - a bit of a gap but nothing that a bit of putty can't fix. The Academy build has a nice snug fit.

Since this Hasegawa kit is missing a few parts, I intend to use the original Tail Stab from the '80s Hasegawa build onto the new Hasegawa build - I need to figure out how to strip off the original enamel paint. I heard soaking in brake fluid does wonders and will not damage the plastic.

3 attached images. Click to enlarge.