I pulled the rockers off cyls 1 and 4 (easy to do) on my 4 cyl; it juuussst wasn't able to start then. Perhaps it would have with a heavier flywheel and/or with DoD that disables after it's started. So no road test of it.
There may be a good reason why there are no factory 4 cyl DoDs on the road. I have read that the mfgs are looking at it...