Hi Pawel, I forgot I had a drop box account so I'll just need to figure out how to post pictures soon.
I tested attaching a drop box picture of my AH-1S(Mod). If you are able to see it, let me know. If you are able to see it, I know, it was pretty worn out, but what do you expect, its an old Vietnam war veteran, I found numerous bullet hole patches all over it.
As mentioned I used Special Hobby’s 1/72 scale M28 turret to 3D print a 1/48 scale M28 turret. It’s pretty low clearance under the turret to get a good picture and I did look through all my reference material for the underside and no luck. You might get lucky google searching for pictures of AH-1s that are on display that are elevated up in the air. There are about 75 or more at VFW posts here in the United States. Wikipedia has the listings of Cobras on display. I’ve seen some underneath M28 pictures, but can't remember where. The AH-1G, AH-1S(Mod) and AH-1P are the only Cobras that used the M28 turret.
I got out of the US Army right before desert storm and I’m not in contact with anyone who served during Vietnam. I do know people, one was a Cobra crew chief, but I haven’t seen or talked to him in 40 years unfortunately.
I too am working on special hobby’s 1/72 kit, although it’s the AH-1S(Mod), they label it a Q which is not correct though. The Q was a development model for the TOW system and not a production standard used by active US Army units. The US Army used the S designation on all Cobras after the G until 1987 I believe and designated them P, E and F thereafter. The (Mod) stood for modified at the time and that’s what we wrote on our log pages as the model series.
Pre and post redesignations: AH-1S(Prod) = AH-1P, AH-1S(ECAS) = AH-1E, AH-1S(MC) = AH-1F. (Prod) meant production, (ECAS) meant Enhanced Cobra Armament System and (MC) meant Moderized.
What kind of primer are you planning to use? I only use Mr. Hobby Mr. Primer Surfacer 1000 on my kits from now on thinned a little with leveling thinner. I might use 500 thinned a bit more, but it absolutely smooths everything out. Depends on how much scribing and sanding I do.
One trick I use because I hate sanding and filling is to use adhesive aluminum tape especially on the tail rotor drive shaft cover. You can also make panels with the tape. Use a pounce wheel on the back side for the hinges on the right side of the tail rotor drive shaft cover, or for rivets. It works best with paper backed tape or foil. I use the same method making panels. The aluminum also works great to weather the paint for exposing bare metal. I’ll have to post some pictures of it, works great.
Tom