I forgot to mention, the cab

1

So I have a Carvin V412 cab from the mid 80s, with Celestion G12m-70's. These aren't very good speakers, so I figured I'd replace them. I'd like something a little more sensitive and preferably a bit less scooped in the mids - they also sound a bit harsh to my ears. I'm using a Peavey 5150 II, for thrash metal in the vein of late 1980s Metallica.

I was thinking maybe Vet30 and British Lead 80 in an X, maybe?

2

I forgot to mention, the cab is similarly sized to a Marshall 1960a and like the 1960a it's closed back. It's front loaded, though.

3

I think I like your Vet30/Britt Lead idea ... especially if you tune to Eflat or below.  It's not a combination I have tried, personally ...

If ya go for it, be sure to post back here with your results!