great looking model you have there,
however the ammo tubes are not accurate if its a british 17-pdr achilles.
they are US tubes for 3' shellls i believe, but i know one thing,
they were never used in 17-pdr vehicles, as 17-pdr shells didnt fit in them.
british vehicles had different ammo racks, with just the shells in them.
check out the AFV interiors site, theres some pics of what i mean.
other than that its looking to be a great model!
cheers
joe