Buy a Spyder E-trigger.
Not designed for full auto modification.
In general, Spyder's "walmart" series are not that well built. They tend to be worse at performance and durability than even their "clone" counterparts. A much better alternatives are the Azodin blitz and Smart Parts Vibe, which cost slightly more, but will perform much better.
the only legal way is to put in a registered class 3 auto sear
Sadly JT did not put the ability to make it full auto. The double trigger style allows for fast shooting. JT has however released more markers with this desired feature.
You need to contact the BATFE for the appropriate paperwork first.
The batteries make the gun go full auto.
The mode your referring to sounds a lot like "NPPL mode". This when you fire semi auto for 3 shots and it then turns into full auto. Sadly the E-grip does not have this mode, though you can put it into full auto mode.
The Spyder RT is good, considering the price. I picked it up yesterday. I have just been playing around with it, because i have no CO2, but the rocking trigger is really nice and you can make it seem like it's on auto with it. The settings: 3 burst, 6 burst, and auto, are really good, but it sucks because you can't use them in parks. The only thing that you will need to upgrade is the feedneck, which sucks because it adds like 2 or 3 inches to the barrel. I haven't tried the compact (I've just heard this from a lot of people), but I thought this could help.
yes if you don't have the full amount-no if you have the full amount and the installments carry a high rate of interest.
About $220,000.
You need to contact the BATFE so you don't end up in jail
Yes and no. You can not turn it in to a full auto by dropping in your own DIAS or milling it out to take the M16 parts. If you want to legally turn it full auto you will have to purchase one of the few and very expensive registered DIAS or lightning links out there. Or if you are really adventurous and looking for a new job go through all of the paperwork and the rest of the process to become a manufacturer and you can make full auto weapons for the police and military. You can not turn it in to a brand new full auto gun however as the time to register ones by "civilians" has long passed. (1986)