Moondog

Anybody have recommendations for a Picatinny or Weaver mount? I bought this one but the bottom is too wide and site astride the sighting grooves. My gunsmith says this and mounts made for round-top receivers will sit a few mm above the groove, which isn't secure because the screws won't have as many threads in the receiver. All of the Benelli M2 rails I've seen are for the Tactical model with ghost ring sight and are too short. Or they appear to be for the SB models with a round top receiver.

Since its aluminium, should I go with 4 holes instead of 2 or 3?

I'm planning to drill M2 Field to add a Picatinny Rail for a 4x scope for deer hunting (specifically a UTG rail for a Mossberg 500 Rail). Does anybody have experience in drilling the receiver? Are there any special considerations such as depth or bit type or size that I should be aware of? I'm planning on using an M5 sized bit and thread tap.

I recently purchased my first shotgun, a Benelli M2 Field "American." Until I saw it on sale at Bass Pro, I'd never even heard of the "American" edition and could not find any vidoes on YouTube for that particular version of the M2 Field. So I've uploaded an unboxing video of my own. I have to say, I'm generally pleased with my purchase. My interest is in clays and possibly 3 Gun eventually so I plan to make modifications soon.

I've seen photos of a decal/sticker like plastic sticker that covers over the Lifter preventing Reload Bite as well as offering a slightly slicker surface to slide the shell across. I haven't been able to find the forum or thread where I saw it. Does anybody have some info on such a mod?