All the large CV's were built on the East Coast.
Yep the big CV would be difficult - some ideas
1) either need to use Sen-Toku launched planes carrying an 800kg each (maybe 1-way trip to increase chance of surprise, and detachable floats to increase speed (Seiran with floats was 295 mph, without floats 360mph) - probably need a float-fighter version of the seiran to escort them
2) Apply full pressure to the RN, take Colombo and then to Madagascar and South africa, then use the seaplane tenders and carriers in the atlantic
3) use submarines to refuel the Emilies (might be possible to launch on a 1-way from the pacific on seaplane tenders, fly across canada to east coast, perform the raid, then refuel at submarines in atlantic, then fly to france) but this way there is no way to escort the emilies (so it really would be like schweinfurt/ploiesti)
option #2 was a big concern for the allies after the IJN indian ocean raid. if the 6 USN carriers were sunk, it would be plausible