Aluminum or steel for custom transmission adapters? Woe is me.

[Matej]

Good day friends,
In the near future I will be making my own brackets to move the transmission crossmember forward, and also a bellhousing dust shield/adapter.
However, I am undecided on whether to use 1/4" thick aluminum (basic 6061) or 3/16" thick steel (general purpose).

The brackets would be similar to this, except I will use angle aluminum/steel to make them more sturdy. I also plan to still be able to utilize the rear transmission crossmember hole bolted to the front mounting mounting point.


As for the bellhousing adapter, only about four bolts would bolt directly to it, as most of the bellhousing bolts line up and will go through to the block. It will be mainly a dust shield to cover up a couple openings around the starter area.

I am leaning towards the aluminum as it is prettier, lighter, and will not rust.
At the same time, I am a bit paranoid that it will not be strong enough. What do you gentlemen think?

Thank you for any input.