@oriskany, did do a reply on 24th on your question on 17pdr H.E, virtually finished it but time ran out on me.

So the Centaurs you mention with the 95mm Howitzers which were in fact the only version of the Centaur to see combat under that name. The reason I say that is, many of the original tanks built as Centaurs had there Unreliable and under powered liberty engines replaced by the meteor and renamed Cromwells.

95mm Howitzer were to equip both used to arm the Churchill Mark V and VIII, the Cromwell VI & VIII .

Bit of a strange beast the 95mm Howitzer

to quote wikipedia ‘The Ordnance QF 95 mm howitzer was built up from a section of a 3.7-inch anti-aircraft gun barrel, the breech mechanism of the Ordnance QF 25 pounder field gun/howitzer and the recoil mechanism of the Ordnance QF 6 pounder anti-tank gun’.

They did try and produce a towed version based on the German Sig 33 but didn’t iron out the bugs before it was declared obsolete.

As for the 17dr HE the original problem is that to survive the stress of the high velocity 17pdr the original explosive charge was actually smaller than in a standard Sherman 75mm’ 15lbs TNT at around 13.34lb so wasnt particularly popular with tank crews , even when reduced charge shells became available it wasn’t much better at 15.4lb. So generally when shooting at infantry the Sherman 75mm worked better ,  British crews in Italy were more than happy with the 75mm particularly in the mountainous terrain they usually ended up fighting in. It does appear that the 75mm, use as artillery was never taught in Normandy as it was with the 8th Army in Italy.

Now as for how much the 17pdr H.E round was issued here are some figure and draw your own conclusions

1942 only AP/APC produced 116000/6000

1943  AP/APC 863000/834000 for H.E. 67000

1944 APC/APCBC 679000/510000 , the new APDS 37000 and H.E. 100000 and H.E. RC  160000

1945  it evened out with APCBC/APDS  103000/160000 to H.E. RC and the new H.E. HC super at 63000/145000

Hope that helps.