For what it's worth, here's my experience with two, 1999 6BTA 330hp engines. Mine are probably very tightly packed into the ER compare to the Selene but I can service all the regular needs myself. The biggest issue in six years so far was the tight fit did not allow the proper drain angle for the wet exhaust mixers, resulting in a pocket of raw water never draining after shut down. One day, I noticed raw water slowly running into the bilge from the corroded mixer. Luckily no turbo damage. Surveys during purchase never unwrapped the heat insulation or looked there so now I inspect annually. Seaboard Marine (SMX) custom made beautiful replacement mixers to solve the issue. Also, I removed the fuel coolers due to corroded hose ends and for easier impeller access using the SMX replacement kit. Latest issue was a weld separation in the fuel return manifold and that's when I learned Cummins is not making replacement parts for these older engines. That said, I've been a fan of the reliability and have been able to find replacement parts or services to repair broken parts. Just know you need to stay limber and as previously noted, plan on bilge yoga
