Here is what I have running on my Glock 34, which is currently 100% production legal, and has been verified by one of the top RO's for the NW section of USPSA. The Glock 34 was designed, size wise, to fit into the prodution "box", so I run it with standard base pads (extended would be pointless anyways, 10 rd. mag limit). Here is the rest:
-Scherer plastic butt plug (weight < .1 oz)
-Tungsten guide rod (weight ~1.6 oz)
-15 lb. ISMI spring
-Standard slide release (replaced extended)
-Extended magazine release, Glock OEM plastic
-Warren/Sevigny fiber optic front, black rear
-Competition plunger spring, striker spring, and trigger spring
-Polished internal components
-Stock "-" connector
The most important thing to keep in mind when conducting "minor" modifications is that you may not increase the weight of your production gun more than 2 oz. over the stock weight.
For INTERNAL modifications, such as the connector, springs, barrel, aftermarket brands are OK... just remember the weight limit.
For EXTERNAL modifications, you may replace minor parts such as the trigger, slide release, magazine release, with a factory/OEM replacement. That means that your Vicker's magazine release would be against Production rules, as they are currently written. The Glock extended slide release, on the other hand, is definitely legal. Also interesting to note, is an exception to that rule: grip plugs are LEGAL, according to the USPSA rule book, "external plugs which alter the grip profile or extend past the bottom of the grip are PROHIBITED". After getting clarification during a regional qualifier match from a reputable source (Production Master class, RO), this means a flush fit plug is OK.
That being said, nobody cracks down on such minor mods at the club level. The only time you are going to have your gun weighed, or examined for legality at all, is at a national qualifier, or major state tournament (and that's even a MAYBE). That doesn't mean you should try to bend the rules to your advantage at the club level. It just means that your Vicker's mag release will be fine, until you get yourself the Glock OEM extended mag release.
All the little technicalities that the average "Production" competitor worries about were not made to stress the average shooter. They are in place to keep the A, Master, and Grand Master shooters on an even keel, where every little bit can mean tenths of a second. That being said, be familiar with the rules because it can never hurt.
Always remember, the most important thing is TECHNIQUE, not parts. I will admit, I got caught up in the excitement of maxing out my production gun, technically speaking, but it is a one time booster. Practice is what we all need to continue to progress, more than anything
Sorry if your face is melting from my long-as-hell comment, by the way. Good luck!