Need advice before I pick up my TT It's a 750 tow

I good buddy of mine just had the noisy lifter issue on his 5.3, his has 237k on it and the lifter issue got worse over the last year. A few weeks back he noticed that the oil pressure was lower than it should be also. He replaced the crank mounted oil pump with some improved (maybe Corvette) type and the oil pressure is back to normal and the lifter noise is completely gone. It sounds like a new truck again. He said it was a pain to change but well worth the trouble.