Apparently "All the Above" - and more
Donny, take a look at my 22 Squadron RAAF reference pics
for this build: their "glass-nose" Bostons (and so will mine) definitely have the 20mm cheek paks. Although it looks like most of theirs were indeed "solid-nose" gunships, of one type or (at least two) other(s) - only the earliest of which retained the cheek 20mms. In short, it looks like the RAAF had every "flavor" of A-20 the USAAF did - and maybe a few additional, custom field-modifications, to boot.
I have more pics of the 22 Squadron gunships - undoubtedly present in quantity at Bismarck Sea - and an article describing and analyzing them in detail, about ready to post.
Meantime, as always, Thanks for the compliments, and encouragement, Don!