Instead of replacing the people in the cockpits… add the missing exterior snowspeeder to the cockpit angles.
I am pretty sure the actual cockpit used to film the scenes was just a sort of torpedo shape. There was not any snowspeeder attached to a gimble.
The ones on the hoth set were mounted on forklifts if I recall correctly but they were not used for the cockpit stuff.
They used the full size snowspeeder prop for all the cockpit shots
