Definitely tight, but I do feel like it all fits. It's not as easy to service things as an LA, but it's the nature of the beast I guess. The only way I see to fix some of those issues is a COC kit and I don't have the funds for that.
Holley's instructions say the DS header has to be bolted up before dropping the motor in. Steering box has to be installed but no column as the steering shaft is captured by the headers so it has to be installed afterwards.
Make sure you do the dipstick while you are fitting the header, I know I can't get mine in with the motor installed and I'm not sure it can be done with the header bolted up either.
Make sure your mounts slip into the saddles on the k-frame. Easiest to do it when they are loose rather than with the motor hanging above you.