spark plugs of right heat range

ok now we got mainly everything else solved, we are putting new plugs in since these ones got oil soaked from the valve cover. we had the ngk v-powers but im not sure if they did so great. maybe because they were the stock heat range, i dont know. the car currently is not running an intercooler since it was bought that way and we were intending to buy one but with all these repairs its getting held off. hopefully we can get something thats like 1-2 ranges colder at a parts store. but does anybody know what heat range and what plug would be best to put in a 420a turbo? if you could even give me the part number then itll make it even easier since guys that work at parts stores really have no idea what im asking for.

NGk BPR7ES plugs, same ones the stock turbo's should use

but the spark plugs are the same length? were not going to run into an interfernce problem and have the piston go through the spark plug or touch it right?

if they are the same lenght as the ones that were previously in it and you had no problems with the piston hitting them then its ok. lol

well whats in it right now is the bkr6e-11 which is for the stock 420a. i wouldnt have a clue if the turbo plugs are the same length as the 420a. and since the parts stores dont carry the bpr7es in stock, i guess i could just pull one of his plugs take it in and check the length on something they have in stock for the turbo motor.