1969 Dart 340 cam selection help !!!

Ok so not a .600 lift cam.
He said he wants to make it so it could handle a .600 lift and maybe go with something that has only a max .550 lift.
I'm going to go talk to him on saturday and find out :
1)why we can't use the connecting rods
2) pick out some parts
3) give him some money

Someone else mentioned the lunati voodoo camshaft.
I took a look at their site and found the :
20200712 that is a hydraulic
Roller with @50 231/239
Lift .535/.550
Rpm 2200-6200
Requires 2800 stall speed ,9.5:1
Compression. Likes upgraded intake, carb and exhaust.
Has anyone used this model lunati ?
.