Quest Master wrote:The waist gun sighting station that Jay has for sale is very similar in appearance to the tail sighting station....but I would like the correct 2CSR3B3 for this tail section restoration.
Have you talked to Carl Scholl? You might have to make a trip out to the dessert and sort through them, but Carl should have a -3B3. The -3B2 Jay has would be just fine for your purposes though; externally, all of the pedestal sighting stations are virtually identical.
In fact, the sighting station shown above in FIFI's tail compartment is not a -3B3, or a -3B7. Here's what a 2CRS3B3 looks like, and how to tell them apart from other sighting stations:


The easiest way to distinguish a -3B3 tail sighting station apart from the others is to look at the "computer" switch at the bottom. The -3B3 sighting stations will have a large switch guard over it, as shown in the pics below. This switch guard is unique to the -3B3 sighting stations, none of the others have this.




As the war progressed, updated models of the sighting stations were released, and the "new" sighting station for the tail was the 2CSR3B7. The "computer" switch was eliminated on the -3B7, while all others still retained them, and all of the pedestal sighting stations (including -3B7) now came with a mic switch.
Here is a -3B6 sighting station for the left blister:

Note the mic switch, which none of the earlier models had:


The "computer" switch (no guard):


This -3B6 is NOS, and still retains the original tags (gotta love that!)



And in case anyone wondered what the B-29 gunners saw looking through the gunsight:


Good luck with your search! None of mine are for sale, but I'd give Carl a call, and again the -2B2 Jay has would be just fine--it's safe to say only a few of us would ever notice the difference