" which brings me too and you probarbly know this, the MKVI was a purpose built gun this had the advantage of reducing the overall weight of previous MKs(which were all conversions of naval guns)by nearly 5 tons, hence the narrower wheels..."
and also the Mks VII and VIII on carriages MkVI,VII,VIIa. Of the Naval gun conversions the weights varied depending on the carriages but some Mks I-V were over 13 tons so a 5 tons difference is about right. The upper carriage on Mks VI -VIII traversed so a little more space between the wheels was needed. To my mind the carriage has a little of the look of a WWII 25 pdr from above but of course larger. The normal emplacement was as in the drawing in the first post and was a Vickers platform which was partially buried and enabled accurate fire and small corrections. It took a long time to install and any major changes would require a lot of digging. Rather than large wheel scotches these marks of howitzer should have the visible (above ground) parts of the Vickers platform to look authentic. When conditions didn't allow the Vickers platform to be used I believe wheel scotches were substituted. Most European theatre emplacements were heavily camouflaged with a canopy, nets etc and the guns not just stood out in the open. The recoil because of the efficient recuperators was nothing like as great as the Mks I-V.