Ok it is a home guard anti invasion version of the universal carrier but not with a bofors or two pounder. It had a pretty odd weapon fitted that eventually ended up with the RAF for airfield defence.
Well, “Bofors 40” is a bit vague, and maybe we should have stated from the onset wherever we mean the antiaircraft “QF 40 mm Mark VI” or the antitank “Ordnance QF 2-pounder Mark IX on Carriage Mark I”, since both are Bofors designs in the same caliber (just not the same cartridge though- one is 40×364mmR while the other 40×304 mmR respectively)
As for the mystery vehicle, your mention of RAF field defense made me think of the Northover Projector, but after I took a long second look at the barrel I became convinced that is in fact the so-called “Smith Gun”, an ad-hoc 3-inch smoothbore AT gun used by the Home Guard.
Wingsofwrath I thought that might help.
It is indeed a Universal Carrier equipped with a Smith Gun. A truly frightening weapon (whether for the crew or target though is debatable).
From what I hear, it was dangerous to be within 300 yards of one such contraption, regardless of the side you were on, because it’s projectile managed rather creative trajectories which usually had little to do with your aiming point…
Anyway, since I’m assuming it is now my turn to post, here is the next riddle:
T4 Medium Infantry Tank, I have seen a very similar photo to this but the tank has a big T4 painted on the hull.
Similar to the T4E1/2 Cavalry Combat Car
You are absolutely correct!
In fact the photo you saw is exactly this one, but I removed the big “t4” marking from the hull, since I thought it would have been too much of a giveaway. Not that it mattered in the end…
Please proceed with the next riddle.
Your image is much clearer than the one I have seen which looks like it was photocopyed from a book.
Try this rare piece. Vehicle and device if you could.
That’s very simple my dear Mr. Leccy: what you have in your picture is nothing but the Sherman based M32 Tank Recovery Vehicle equipped with the T1E1 Earthworm anti-mine roller.
Subsequent incarnations of this design lost the middle roller and the crane.
Darn way too easy, thought the roller might get someone as they had different numbers of rollers on the different models. The M32 I thought would be fairly easy.
Your turn.
Ok then, this should be pretty easy to guess as well. Unfortunately I lost most of my best quiz pictures a few months back when some guy filched my laptop, so this will have to do for now until I can remake my database of obscure vehicles
.
Nearly conned myself that this was a T26 or Vickers 6 Ton. Indeed it does share the same lineage with those two vehicles.
I believe it is the Polish 7TP jw (or Single Turret model).
And right you are!
I confess, I was aiming to bamboozle people into saying Vickers 6 ton or T26, but apparently you are much too attentive for that.
If you know what to look for it’s fairly easy to spot the taller rear deck that’s so characteristic of the Polish variant.
As per custom, it’s now your turn.
Trying to confuse people is good, I noticed the gun mantel being an odd shape for a T26 or Vickers way before noticing the rear deck ‘doh’.
Lets try this easy one
Hmm, if I’m not mistaken, your mystery tank is the Italian Carro Veloce CV-38 also known as “L3/38”, a torsion bar variant of the L3/35 tankette which was also usually armed with a single 13.2 mm Breda M31 machine gun, but this particular example seems to sport the same twin 7 mm Madsen machine guns as the earlier model.
Edit: interestingly enough, this model was initially manufactured for export to Brasil.
Lol said it was easy, yes the L3/38. I have read they were destined for Brazil but the only pictures I have seen of Brazilian L3’s are the L3/35.
May have to start getting harder then.
Indeed, it seems we should be kicking this up a notch. Well, here you are then:
looks easy,…
but looks can be deceiving,… 
Matilda Mk I
Bingo!
My offer was indeed the “Tank, Infantry, Mk I, Matilda I (A11)” as it was officially known, a rather odd little vehicle which has absolutely nothing in common with the better known and more widely used " Tank, Infantry, Mark II (A12)" aka “Matilda II”.
Your turn, my dear Mr. Gumalangi!
Thank you sir,.
please ausf it 
Panzer III Ausf M in the Soviet Union fitted with Schurzen