Marauder Gen 1 vs. Gen 2

What's the difference between the two generations? Will Gen 1& 2 stocks interchange or are the differences internal. 

I know they changed the receiver mounting screws from two to four so the pressure tube mounting holes are different and the tubes are

therefore not the same but I believe the diameters and lengths are similar at least the portion that fits in the stock.
 
Different Trigger group AND placement ... So Trigger assembly or Stock DO NOT interchange.

Different air tube being gen one is a 3 screw receiver & gen 2 is a 4 screw ... So different tubes and receivers DO NOT interchange

Valves slightly different ... You CAN use a Gen 2 valve in a Gen 1, But CAN'T use a gen 1 in a gen 2 without modifying it

Velocity adjuster caps completely different
 
Barrels on the Gen 2 were considered "Better". Apparently, Gen 1 barrels were a bit of a lottery on accuracy. some good, some not so much. I can say, my Gen 2 is a comfortable 50 to 75 yard gun. Not a 100 yard gun, but nice at the shorter ranges. At 25 to 50, quite accurate. New barrels are supposedly on par with higher priced European stuff. Whether or not it's true, i'd have to see it first. Still quite happy with my Gen 2 after 10 years
 
I think the hammer spring guide is also different. If you end up changing the HS you may consider a Hill HS guide for the gen1, as it will accommodate different diameter springs. For some reason the depinger is ringing a bell, pun intended, between the two gen’s, but cant remember for sure on that.