Is it worth the $ to build a 5.9 Magnum (or LA 360) without making it a stroker?

My sons 360 engine that run 10.20-10.30's is shifted at or under 6800 RPM so we don't consider that real high. My 422 that runs 9.42 is shifted at 7000 rpm. Matts engine started making a noise right after another 6.54 pass so we parked it in October and haven't torn into it yet. This engine was orginally build with a Racer Brown 520 lift solid lifter cam and he wanted a 600 roller so I with the short block already together I didn't tube the block. BIG MISTAKE as we had oil gushing past the 3 different styles of roller lifters I tried. I finally block the oil off to the one side and oil pressure was good but I knew we were still wasting oil badly one the one side. I'm betting we slightly hurt a bearing but like I said he caught it and ran my car for the rest of the weekend. I will NEVER build another 360 without tubing the block and his will be tubed real soon.
What is tubing the block and what does it do?
I am an amature here, so any info will help me follow along...........