Lippy, mounting the accumulator was no problem for me. Mine sits where a under car exhaust muffler would sit. It is piped via SS braded hose. there is plenty of room in your ERA for one. Maintance is the same as before the accumulator install.
Oil pan, top end work, all the same as before. If I had to R&R the engine, the only disconnect point for the oiling system would be the original filter point. KISS, remember.
Stick with Brents susgestions, you won't go wrong