The RX4 is a longer motor. If you want to fit it you will have to modify the chassis.
If this is allowed, then I suggest you buy a Ninco "Spanish Motor" adapter, cut out the appropriate rectangle from the chassis and glue it in.
If not, buy a Ninco Scooby and buy the alternative chassis, which accepts the old mounts.
McLaren
If this is allowed, then I suggest you buy a Ninco "Spanish Motor" adapter, cut out the appropriate rectangle from the chassis and glue it in.
If not, buy a Ninco Scooby and buy the alternative chassis, which accepts the old mounts.
McLaren