A318 vs 318LA Alternator Mount

[64Powerwagon]

Does anybody know if these head castings are the same between these two engines for alternator mounting bracket location?
I have an A318 with double belt pulleys and want to upgrade to 70's square back alternator. The only model number ( ACDelco 3342211 ) having the 2V 1/2" pulley and center of 1st belt distance that works with my poly engine with factory mounting. (Also thinking of using PowerCraft squareback with internal voltage regulator.)
There is no provision to adjust the alt. forward to align pulleys with the forged bracket. Any suggestions would be welcome.

[DocsD200]

Did you figure this out? I am wanting to upgrade my alternator as well.