Vandies a good fit ?

Upgrade time for my speakers. Heard Vandersteen 2CE Signatures and liked the sound, but I can see 2 possible problems.
1. I only have 26 inches from the rear wall. So the 10 inch thick Vandersteen's will have 16 inches of air behind them.
2. My amp is a 45 watt tube CJ MV-52. Passive preamp. CD player and tube tuner. I listen to classical and jazz at low to moderate levels.
Will the Vandies work?
You'd probably do better with a pair of the 1C's and one 2wq subwoofer. That's what I'd do in your situation...
18" from the back wall seems to be the magic number for Vandy 2 Sigs. Can't comment on the power issue.
consider medowlark kestrels.
i second to 1c as a better choice with sub for 45wpc amp.
Beacuse of which issue: 1, 2, or both?
i would look at stand mounted speaker...the vandies bottom end may overpower the room.

Yes, for both reasons. I think it'd be easier to place the 1c's and one 2wq in a small room. As far as power goes, if you incorporate the vandersteen crossover and sub, the mains (1c's) will be very easy to drive. That should leave you with plenty of headroom for most crescendos.

I'd also recommend getting an active CJ preamp to use with your MV-52. Or you could sell the passive pre and the MV-52, and pick up a mint used ARC CA-50. Since you mentioned space is limited, this would save you some shelf space, eliminate one interconnect, and give you the convenience of remote.
If I remember correctly, I believe Vandersteen recommends that the 2c's be placed at least 20" from the back wall and 32" from the side wall (measured from the center of the the speaker) and that they receive at least 40 watts of amplification, so you might be set on both accounts, though it certainly would be a good idea to double check before you made a final decision. When I got my 2c's I ran them for a bit with my old 50wpc ss integrated just for fun and everything was fine though they clearly prefer my current 100 wpc amp.
The bad thing about all Vandys they don't sound immediate and continue to sound when they should stop i.e. there is a presence of parasite resonances probably due to cabinetteless design. To produce quick and controlled bass the driver realy should be firmly attached to the cabinette and not on the joists as Richard developed. That might work for small drivers maybe. They do actually benefit from higher power, spl and tougher drive despite sounding clean and clear with lower-powered amps(the good thing is their stable load). Whenever I tried to hook them up with more powerfull amplifiers that problem of vibration traces partially dissapeared.
There are number of tweaks possible with vandies but eliminating resonances may cause depletion of their excellent imaging abilities.
So believe it or not, but to my tastes a pair of 1c with a pair of 2wq may even work better than single 3A's in some cases.
IMHO, the Vandies are very fussy re: room and placement. While many people seem to like warm tube amps with the Vandersteens, and I think your c-j falls into that camp, I think it might be too much of a good thing. While the c-j is up to the job, a bigger amp will be better. I'll second Marakanetz' Meadowlark suggestion.
Good gravy Marakanetz, there is nothing mounted on the poles that support the grille cloth in any of the Vandersteens. The bass drivers are located in the cabinet below. Go to the Vandersteen web sight and look at the speaker. The drivers are mounted as solid as in any speaker. The are not "Cabinetless" They are baffleless! This means that the CABINET is as small as possible around the speakers drivers to prevent interaction. Something a lot of higher priced manufacturers could take note of!
My 2Ce are at least 4ft from the front wall. Approx 6 ft apart and about 2ft+ from side walls. These seems to give me the most transparent sound with solid low end. Any closer to the front wall and the low end gets to be too much of a good thing!

Power wise I would not think you enjoy the full benefits of a 2 Ce till you get to about 100W. I have been through this grindmill already, first with a 60W SS amp, then to a 80W Rowland stereo amp and now to a 245W Rowland bridged monoblock. The progression is tremendous - with sufficient power/current (whatever it is!) the sound just opens up: the soundstage extends left and right, the air and transparency, depth and low end is just night and day improvement. The sound is sweeter and complicated passages are not compressed or screechy. The speakers just love high end upstream, and you don't get your money's worth out of the 2Ce till you hear it with a good setup. IMHO 45 watt is not what you could live with once you hear what this spks do when they are cut loose on a good powerful pre/power amp combo. Don't believe otherwise, you'd just be fooling yourself.