^ I understand they can have higher rpm oiling issues since the mains are about the same size as in a D-9 Cat.
Are there any mods - other than a high volume oil pump like you spec'd - that help? My old guru used to talk about using 3/8" copper tubing and tapping into a main, using the tubing to deliver pressurized oil to an area that typically caused problems.
I've gotten to the point where I appreciate pretty much all brands of engine and car building and modification. Kinda softening in my older years LOL.
As for the washers on the floor, I watched a guy with a fresh 460 Ford stroker build and a 3-wheeled engine stand dump the whole thing on the floor when it hit a washer.
Made a believer of me in 1)keeping the shop floor swept, and 2) never use a 3-wheeled engine stand
Olds engines were designed to move heavy land yachts effortlessly down the highway. Keep the engine speed below 5000, they will live forever. Chances are, unless you swap in a more aggressive can, there is no need to spin the engine faster than 4500ish. The stock cam will have the engine gasping for air long before parts come apart.
If you want to beat on one and have it live a long life, there are a few things that need to be addressed.
The absolute best modification to a BBO oiling system is to machine the crank so the bearing clearance is a little on the loose side. I’m about the biggest Olds fanatic there is, but they do have their shortcomings. The biggest is the rods, while they are forged, they are soft as butter. The cranks are massive and heavy, that much weight spinning around and things tend to move around. If you don’t set them up with loose bearings clearance, they will “clearance” themselves.
The first 455 I built I used a well known Chevy shop. They machinist argued, saying he didn’t think the big clearances would benefit me, and would cause low oil pressure. The engine didn’t last long, I kept finding crap in the oil filter, the oil pressure at idle kept dropping, the oil pressure at high rpm was never that great to begin with. After one summer, I tore it back out to find copper showing on every bearing.
I used a different shop the second time. I found out the owner use to race Olds way back and was familiar with setting them up. The bearing clearance was .004-.005, combined with a high volume pump I have about 25psi hot idle, and almost 60 at speed. I shift the engine at 5600, go thru the traps at about 5800, and this is the 18 year on the short block.
For a truck, it’s really hard to beat a bbo. They don’t have a torque curve, more like a torque plane. The torque start high, hits its peak around 3600-4000, and slowly drop off again to high. Perfect for something that has to pull a heavy load.
I cannot wait to hear people's comments about the Olds in my truck, it's gunna be fun 
