[David_Hayward (RIP)]

To complement and compliment my colleague's very well set out description, the DND (Department of National Defence) papers from 1940 refer to Modified Commercial Pattern. That was at the time when they also mentioned DND-pattern trucks (with the C30S/F30S).

As an aside, and example, the Candian Chevrolet Model 1543 was a 'popular' civvy model, being a 2-tonner with 160 inch wheelbase. There were however at least three known MCP variants as the 1941 Model-on CC60L:

CC60Lx1 = DUAL REAR CIVILIAN WHEELS
CC60Lx2 = SINGLE REAR MILITARY WHEELS
CC60Lx3 = DUAL REAR CIVILIAN STYLE WHEELS

I think that these suffixes were meant to relate to the GM of Canada export destination codes that were suffixes to the model numbers, and used from 1935 to 1958 at least:

X EXPORT DESTINATION CODES AFTER SERIAL NUMBERS:
X1 ANY POINT EXCEPT FULLY BUILT UP
X2 UNITED KINGDOM BUILT UP
X3 INDIA CKD
X4 AUSTRALIA CKD
X5 NEW ZEALAND CKD ALTHOUGH ASSEMBLED TRUCKS HAD “XH”
X6 BATAVIA, NETHERLANDS EAST INDIES CKD
X7 UNITED KINGDOM CKD
X8 ANY POINT CKD
X9 SOUTH AFRICA CKD ALTHOUGH ASSEMBLED TRUCKS HAD “XG”

Known other Chevrolet MCP trucks include 1/2 ton 115" wheelbase Model 1311X3 for India (and alsdo some for the LRDG), 1421 1-ton chassis with flat-face cowl 125" wheelbase, 1531 2-ton 134 1/2" wheelbase chassis with cab including 200 1533x2 for the LRDG.

That said I suddenly realised that I have photos and descriptions of Modified Conventional Chassis in my collection, which should be going into a DVD album in the future:

1542x3 3-ton 160" w.b.
1533x2 3-ton 134 1/2" w.b. with 9.00 x 16 wheels
1543x2 3-ton 160" w.b. with dual perfomance axle and 20x6 wheels and single rears
9543 GMC equivalent of 1543 with stake & rack body with 30.2hp 224 cu in GMC engine
AC-704 GMC 178" w.b. firefighting lorry..278 cu in GMC engine 178" wheelbase
1500 series 2-ton ambulance ..probably 1535 2-ton panel delivery 134 1/2" wheelbase
1600 series 2 1/2 ton aircraft gasser...probably 1663 chassis with cab 163 1/4" wheelbase MAPLE LEAF