[Edit] Deleted because telling Lew how the way he writes his opinions is unbelievably offensive does not appear to help [/edit]
So let's help the OP get what he needs!
Under high gain you are not gonna lose anything under the covers, IMO. So go for it. A couple of suggestions have been given...however - let's talk about going the extra mile for the OUTSTANDING result!
I have not been to Japan recently, but I'm pretty sure they have drills.
1. Get the cover of choice.
2. Press the pickup into the cover
- The goal here is to mark the INSIDE of the cover with something
- You could use a little nail polish or something to get pretty exact with that second row of screws
3. Take a drill and drill the extra holes!
- Tape the other side like it is paint. Likely don't need to but you never know
4. HEAVILY pot only the pickup
- I bet it will be fine.
I have had unspotted pick ups, P-90's Semi hollows and sorts of things playing in hard rock situations without problems. More about position than anything else, occasionally frequency. Yes - potting can help or completely eliminate, but I find the need for it is usually way over-estimated.
Easy enough to try it with out and do over if needed.
Plus - when done - there is the bad@$$ factor...