Aluminum diff covers

[68panelman]

Both trucks of mine leak a little from the rear diff covers and I'm wanting to get aftermarket finned aluminum. Sure I can't straighten out the old ones and apply copious amounts of silicone and be done with it, but not worth the effort.
My 70 Blazer is the easy no brainier, large capacity cover, but my 2wd 67 is in question with this type of finned cover, it seems to protrude further out then stock. My question is it seems the track bar would hit. I called suppliers and of course their staff can only read off a computer screen just as I am doing the same, given the same information I've already read, seems to be the norm nowadays?
Any suggestions as to types and brands?
Thanks, Mike