It was practice to run an opposite engine on the -436's during a ground run so that the enormous strain on the nose gear was relieved.Never used as comparison,just to stop ripping off a nose tyre or damaging the gear mountings etc.
It was 'FP and part of a TWA wing was grafted on and plates added "wedding cake " style externally.
The Conway was a very good engine for its time although a little thirsty over the fans.
Straightfeed