I'm very happy with the performance of Alclad in this first test of it. Prep was long, but seemed to have paid off. Everyone that's seen it in person has commented on how real the aircraft aluminum looks.
Painting steps:
1. Standard seam sanding and such, but I didn't do any specific prep to the bare plastic other than fill and sand like for any other paint surface.
2. Prime with Mr Surfacer 1200 thinned with Mr Leveling Thinner. Laid it on fairly thick in several coats. Sanded this one for quite a while. Started with 1000 grit and then 2000 grit paper from Wal-mart (dirt cheap and effective), then on through 8000 in micro-mesh. Got very, very smooth.
3. Sprayed on the Alclad gloss black base. I stirred the heck out of it with the badger electric, but it still went on fairly tacky after 24 hours. Did a lot of research on it, and several top car modelers wouldn't spray on anything but a tacky black base due to adhesion issues if it was fully dry, so I gave it a shot... and the alclad went down perfect and very tough. The alclad site itself says not to mask over the high-shines, but I masked the heck out of it repeatedly and only had paint pullup in two small spots.
4. AA aluminum, followed by standard aluminum on the outer gun panels, and white aluminum on the inner. White was also sprayed on the control surfaces, and dark on the flat tank. Mr Color OD is the stripe, with Tamiya red, yellow, and black for the other colors, all thinned with MLT.
This kit fights you in countless small ways, but only small ones. The 'big' things... wing roots, fuselage joints, dihedral, front canopy fit, etc., were all flawless. I can put up wth a lot of fiddly issues if the big things go down well.
The Kitsworld decals for the plane spec markings were the best I've ever used. Period. The Eagle Cal decals I bought for insignia replacement looked great but simply wouldn't stick. The kit decals I went back to for insignia stuck fine.
I should have gotten a bit more aluminum on the brass barrels, but it's only apparent if you look at the bottom of them very closely. I made a tactical error in assembly... it looked like the small piece with gun port holes was going to fit well in testing, so I left it and barrels off completely so I wouldn't risk damage during main construction. They didn't fit so cleanly once the wing was together, with a noticable gap, and also sliding the barrels through scraped the paint off. Waste of time. I recommend fitting the barrels, fitting the gun port plate, correcting the seam, and just be careful with the barrels sticking out.
Fitting the cowling is a disaster if you try to leave the rear ring on the engine.
Last thing you might notice from the pictures is a missing starboard wingtip light. It just vanished. :( I'll likely order the Trumpeter P-47N in the not too distant future and will be able to salvage a new light from that kit (D and N lights are both on the same clear sprue), since I know all the foibles in the kit and can make a better run at a show-quality build. If anyone builds the N in the near future, however, I'd pay a nice fee for a tiny piece of clear plastic you're not going to use anyway. 
In closing, I'm not sure I'd use regular aluminum for an airframe after seeing it in action no matter how beat up the plane is supposed to be. It just doesn't look real like airframe aluminum does. It's great for a few individual panels, but even the beat-up planes of the Pacific theater had a fairly metalic look to them in NMF... they may have been through the wringer with the elements, but there was still a luster under the patina and the grime. I'll have to think on how to approach the N when I build it, as they were all pacific birds IIRC.
Fun build, but very long. Thanks to Doogs for all the tips and starting the Group!