What would be the best plugs to run in some HP500's with Brodix Alum. heads..Would the stock plugs be best or ??

I'm running NGK BKR6ES-11 plugs .

The stock plugs were a tapered seat plug. The Brodix heads run a gasketed plug. If you didn't make many other changes, then you will want to stick with the same heat range. In the Brodix head, I use NGK R5671A-7. That is a gasketed seat plug that works with the Brodix heads. The stock cast iron heads use an NGK BR6FS in a standard plug and a R5673-7 in and NGK Racing plug. Hope that helps.
Eddie

Yes..that's a big help..thanks for the responses..

I have a 540 with Brodix iron heads, I'm pulled a plug (so I knew what to buy) it was a ngk BPR6FS, I went a head & changed them but come to find out the other 15 plugs were Champion RV15YC4..... WTF
my question is am I ok with the BPR6FS NGK's (gap set at .038) is this a safe heat range for a n/a 540 with 600+hp?

thanks

any other opinions