I don’t sweat to much with the details. Being a GM is hard as it is.

IIRC the gameplay loop from Twilight 2000 (and other Free League) is pretty simple and that’s the basis for everything else so remember this one and put the rest in your memory maybe it will come back, maybe not 🤷‍♀️ have fun

The glass cannon recently did a campaign of it that's going up on their YouTube channel currently

I always find it helpful to check some actual play to cement my understanding of certain rules. Although there's no way to guarantee the actual play is definitely correct obviously

If I wanna learn it, I usually have to be a player first.

The few times I've had to be the GM it always comes off the cuff. My most hated thing is pausing a game to look up mundane rules about encumbrance or climbing or anything.

Eventually you'll learn, at most just write down what you should look up later.

1. Read the book

2. Create a bunch of 'test character"

3. Use these test character for a "test one shot" with player interested to try, and understanding that the point of the one shot is to learn to GM the system

It gets easier with each new system. After a while it becomes "ok, so it's approach to skills like in the other system and the armor rules from that other one". What I do when assessing a new one is:

• how the basic mechanic works?
  • we build the roll only from PC or also consider gear?
  • how modifiers work? + to roll, step up dice, another dice, move TN?
  • what are the odds of success, failure and "bigger success" on three edges of of skill - lowest, middle, top
  • what does the bigger success mean mechanically?
  • are there re-rolls/pushing the roll? Does it change the odds or is only a re-roll
• how leveling up works?
  • what is needed to level up?
  • how much does a level up change in the roll odds?
• how does money work?
  abstract vs counting all the bills
• is there anything exotic in the rest of the rules
  things that are there to convey the feel of the setting
  • contacts working like money
  • rules for gear getting used up
  • running out of ammo
  • meta currency
    is it a hard earned boon or "the spice must flow"?

With crunchy systems I'd then forget about the more intricate half of the system, get the game on and try to have combats of varying size during first few sessions. Most of the time, if there's crunch in the system, it's mostly about combat.
Write on players' sheets shortcuts what to roll on doing what. Like next to the gun name "shooting d6+d8".
During first few games when you remember that there was some more crunch in the system but don't remember exactly, don't stop to look up. Ask a non-spotlighted player to search for it but "for now let's roll this and that against that" and keep going.
Keep an eye out if they are getting into the crunch. If they won't follow you down the rabbit hole in a few (3-5. not less) games, it might be that either you get the rules etched in your brain or that level of crunch is just not for this table

And on closing note, as far as I understand what T2k is, I would guess that getting their hands on an MG is not something common in the setting and the complexity of the rules for that are an outlier. I might be wrong, though

I don’t necessarily want to jettison this level of crunch, as I think it’s integral to the tone the system is designed around, but fuck me if it isn’t a lot to keep track of

Allow me to disagree with the highlighted statement. A mistake old school game designers used to make is to try and reflect every fluff detail in the rules. You don't have to differentiate an assault rifle in full auto from an SMG and in most cases, even an HMG. If you go down this route, you will need to account environmental factors, fatigue, time of day... which are also big influencers. But we don't, because that's what randomizers are for. Just bundle the difference in the randomizers.

You'll say, correctly, "getting hit by a .50 cal is a world of difference compared to a 9mm". That's true. That's fiction and setting, though. It doesn't have to be reflected in the rules of simulating shooting the things in a game.

My advice would be to do exactly what you proposed not to: chuck the entire system. Use a generic system instead. Whatever you're most familiar with: Cortex, Savage Worlds, Fate, GURPS...

What is your story about? If it is about handling the gear, then perhaps (perhaps!) keep the OG system. If it's about anything else - a shared overarching plot you'll write with the players; about how the characters react and evolve to their surroundings; about interpersonal drama; base building, you name it - use a different system.

Of the ones I listed, Savage Worlds is easily reskinned, Fate is easily tweaked, Cortex is a toolbox to get your game moving fast just the way you want it to feel, and GURPS probably already has a module for you to use. If you want to bounce ideas with other people adapting to Fate and Cortex, they both have very active Discord communities (I know, information silo, but that's where the authors hang out). Good luck!

P.S.: I just remembered Cepheus (a Traveller retrocolone) has the acclaimed Modern War from Zozer Games. I have played their Hostile (Alien universe RPG) and the ruleset is essentially the same. There is some crunch, but easier than D20: https://www.zozergames.com/modern-war.html

It looks like it and Delta Green lead sales on military RPGs: https://www.drivethrurpg.com/...