I can't say for sure in your case, but I doubt the valve job would cure the high lift flow situation.
And it's very likely you could end up with a can of worms if you start grinding more out of those heads(he said without ever seeing them).

Have you contacted LSM about making you a core?
If you waited until they were filling an order for sb mopar cores, maybe it wouldn't cost that much to have one done with lobe lift, duration, lsa that would work for you.

Frankly, I'd never spend the $$$ for an experiential custom core for something that didn't absolutely require it.

I still say the stocker flat tappet dwell lobes would work well enough to answer your question, and that wouldn't cost any more than a "normal" flat tappet cam(and you could have it in about 10 days).