I need help!!
aluminum will be fine, just get Yella Terra's. I have a bunch of miles on my yella's and they are problem free.
For that harmonic balancer, throw it in the oven @ 250* for 15-20mins get her nice and warm and it will slide on the end of the crank w/ no problem. I did this w/ mine and it went 90% of the way on and didn't need to use the tool.

