After seeing Ben Fulcher's 1/48 Privateer at the OKC contest (which took home some bling from Nationals as well), I was inspired to pull out my Matchbox 1/72 Privateer. After looking it over, I ordered replacement "glass" sets from Squadron, resin engines and nacelles, and Quickboost gun barrels. When I started work on the turrets, I realized just sticking the Quickboost barrels where the Matchbox broomsticks were wouldn't suffice - I needed to build out some detail to the turrets themselves.
Here are the parts I started with for the 2 top turrets:
With the replacement turret, I needed to cut the Matchbox clear part in half and use the bottom half. I filled in the gun slots, as they do not extend down as this part has it. I also thinned the remaining section as much as I could and still get it to fit on the base, so I'd have room to build out details inside the turret. I cut off the barrels, glued the cross piece to the mounts, then sawed the ends off and filed down substantially to make a mount for the .50 cals I manufactured out of styrene. I glued the remaining clear base to the base of the turret, blocked in the slots and painted the interior before I began to work up the turret. I glued the Quickboost barrels to the .50 cal stocks I had built and painted them up, then glued to either end of the crosspiece, after I had seated the gunner. I did need to cut some off of the guns to make them fit, as the space within the turret is very tight. Next I added some additional details with styrene. I used a carrier section of the Squadron canopies to create gunsights. I cut up copper wire, laid it between a couple of strips of crepe art tape and then trimmed, to create the look of a bandolier of shells. The last pic below shows the cut out Squadron turret sitting atop the base - I haven't cleaned it up or detailed it yet, but as clear as it will be, you can see why I felt I should detail out the turrets!