NICSON speed equipment?

Here are a couple of pics of a 331-392 hemi boat timing cover with dog legs. I have seen many sbc ones but this is the only hemi I have seen.

 

Here are a set of spark arrestors

 

NICSON used to be right next door to a NAPA store / shop in santa fe springs Calif.

my own shop was just across the street. circa 1982.....

 

I had a Marine Head for a Ford Flatsix, that was just wall art! Someone had tried to welded it and save it. No dice, Gave it away.

 

For the most part how does one date some of this stuff ?? When were the Nicson years ?

 

More pics please, and what valve covers are those?

 

Old post, but here is a rare early olds timing cover I just picked up off eBay, and for a fair price!
It's going on a 471 blown and stroked olds. Definitely not using the doglegs, but don't want to cut this up. I'm sure I'll come up with an idea for mounting something off them.

 

I have a Nicson front mount and water pump timing cover
on a 392 Chrysler Hemi motor that was used on a race boat.
Nice piece.