Hello RRyan

As mentioned in one of the above letters the outside shape of the cooling fins were a bit different - in a later version.

The one you have is the original one.

Even earlier the backplate was different - and had a 2-piece NV assembly.

The hexagonal bolts for assembly were used in the 60's.

My own MACH 1 is from -55 and still running very fast - which was a trademark of the MACH 1.

Later there came a glowversion which was less succesfull than the diesel.

Use this fuel - and it will run : 30 % castor + 35 % kerosene + 34 & ether + 1 % amylnitrit or -nitrate.
Put on a wellbalanced light prop f. ex. a 8 x 4 Tornado plasicote woodpropeller and you will enjoy !!

My complments for your work.

KR

hld - OY-9901