Early vs Late V8 accessory Mounting

[MReese Wagonner]

So I am working on my 401 for my 1983 Brougham
the 360 had a 3/8 x 6 bolt holding the alternator in, through 2 brackets and the spacer, this is the one the alt swings on at the top
the 401 has a 7/16 bolt in that space
now I thought I have read somewhere they did change that along the way somewhere
What year did that change
so far i have ordered an alt from BJs which they say should work from the '75-'77 years
am i on the correct path
I will drill out the spacer and the brackets if the alt is correct

[rang-a-stang]

You sure the difference isn't A/C vs no A/C?

[MReese Wagonner]

You sure the difference isn't A/C vs no A/C?

Yep , the passenger side head early vs late around 1975 they changed from 7/16 to 3/8
There is no 12si style alternator with 7/16 so I am left to drill out the

[will e]

I drilled out the alternator housing. Easy to do since it is aluminum.

You'll find that the exhaust bolts are all the larger size on the 401 heads too.

And plan on reusing your 360 oil pan. It's notched for the exhaust.