A bone stock bottom end is way good for 500. There's guys who insist the factory rods won't hold up, they will. Any more hp or rpm and you will definitely want to replace them. Same for pistons. You will be good with the Mahle. Either or on the studs. The factory TTY bolts hold 500 on the SRT 6.4 stuff. Usually with "bigger" cams, the VVT is locked out. As far as I know, the stock timing set holds up well at that level. I only have experience with the Milodon swap pan. Have had good luck. I see Holley makes a cast aluminum swap pan with a bunch of extras included. I would lean that way. Good luck with the dipstick. Lokar and Milodon make one. I modded a stock one to work with the Milodon. I haven't really heard any good about the available dipsticks. You can use stock non-mds lifters. Some will use Hellcat lifters. Supposed to be heavier duty.