Time for another update, continuing on with the landing gear bay.
I added break lines to the landing gear and installed them into the gear bay. The lines are 0.015" lead fly wire with fittings made from aluminum micro tubing. I like the effect these give, and it is a pretty simple addition to make.
The gear bay is now complete with the exception of the tires. I'll add those at the end, they are going to require some cleaning up to make them look good. The mold seams will need removed and likely the tread pattern redone with a micro saw.

The legs click into place with some pressure. The fit was so tight there seemed zero chance they would come loose but I glued them anyway to guarantee it won't collapse suddenly one day.

Brake lines added. I considered using micro-tubing for the upper and lower lengths which were not flexible on the real thing, but decided just to paint them silver with black for the flexible hose through the oleo scissors.

Decent view of the gear bay and all of the added wiring detail. I like how it came out, it looks much busier now.
One thing of note. I debated replacing the wheels with resin, but it was going to be tricky. Meng have molded the brake drums into the gear leg unlike most every other kit out there, which just have the legs and axles. This meant I'd either need to modify the resin wheels by removing the drums from each, or I'd have to conduct some surgery on the kit gear to remove the drums. In the end I decided to keep the build simple and go with the kit wheels. They aren't bad, they just are not as nice as the hollow wheels you can source from Eduard or Barracuda.
On to the wings...
I am happy with my putty work. A quick coat of primer showed almost no flaws.

The wings are nice and smooth now, with just a few panel lines remaining. I do need to correct the bottoms.
If you notice the five clusters of rivets in a line towards the rear edge, those will need filled. Meng molded the wing as a P-51D-25, meaning those are the mount locations for the HVAR rails that became standard with this version of the Mustang. It's honestly a nice touch, but I need to get rid of them as "Big Beautiful Doll" was a P-51D-20 and wouldn't have have the zero rail mounts. FYI, the kit does not include HVAR's, just the mount locations on the wings.

All those rivets are gone finally.

This was the only flaw I found. I'll need to sand this spot smooth so it doesn't show under paint. Easy fix.
I'm going to put the wings together and then do the final pass with filling and repairing the seams. It should be easy now that the majority of the putty work is done.
One last note while I am on the wings...
Meng did another small detail that really made me appreciate the detail they put into the kit. While I was hollowing out the gun barrels (so easy to do in this kit!) I noticed something I hadn't before: Meng molded the plumbing locations for the drop tanks.

Nicely done, Meng!
Adding plumbing to the drop tanks will be a snap. I am not aware of any other 1:48 Mustang that the kit manufacturer bothered to go to these lengths to include these little details that stand out. I don't know, I just found that to be a nice touch.
More to come soon. I should have the wings assembled this week.