Hartmut and Dr. Jones mentioned something about a V12 G Wagen when I asked them - possible to go as high as 7.4??

I'd personally go for the V8 55 over the V12 63 but if you want something special I'd copy that Dude from the UAE with more money than sense and stuff my G-Wagen with an SLR's engine
McLaren-powered Mercedes G-wagon spotted... guess where - Autoblog

The V8 is the SLR engine just that it doesnt have forged pistons and other few differences, the G55K can when modified can reach 640hp easily with cams, ecu and pulley, filters, headers and cooling mods.

Right, with a supercharger. I'd get the GV12 if I had the coin, or the G63 V12, simply for exclusivity.

I would go for the G55 just for the engine, you can say its Mercedes's GT1 block of the cars how porsche owners love the 997 engine and thats the case for mercedes enthusiasts.

i would get an armored g wagon and put the old engine from the 190E in it. then i would just cruise down the blvd. doing 25mph. that's just how i roll.

25mph @ 6,500 rpm in the highest gear. I like your style.

An armored B7 G55 costs 510,000 usd.

i don't need the 55k engine. i'll use the savings to get some 26's.

lol Mark