Kind of already coded it myself for personal use, but I figure it'd be good to allow users to be able to use the V3 without Space Age if they either don't own the DLC or are playing a challenge run without Space Age.
I also kind of disagree with the placement of the V3 at Aquilo since it's so late into the game that bugs already stop being a problem altogether. Imo it makes more sense to require Fulgora + Vulcanus tech in order to help with Gleba prior to unlocking the Spidertron.

-- settings.lua
data:extend({
  {
    type = "bool-setting",
    name = "heavy-trucks-v3-without-space-age",
    setting_type = "startup",
    default_value = false,
    order = "a-99"
  }
})
```lua
-- trucks/v3-truck.lua
-- line 4
if not space_age and not vanilla_enabled then return end

-- line 115
local vanilla_packs = {
  {"automation-science-pack", 1},
  {"logistic-science-pack", 1},
  {"military-science-pack", 1},
  {"chemical-science-pack", 1},
  {"production-science-pack", 1},
  {"utility-science-pack", 1},
  {"space-science-pack", 1},
}

local truck_ingredients = space_age and {
      {type = "item", name = "heavy-truck", amount = 1},
      {type = "item", name = "quantum-processor", amount = 10},
      {type = "item", name = "lithium-plate", amount = 50},
      {type = "item", name = "tungsten-plate", amount = 20},
      {type = "item", name = "low-density-structure", amount = 20},
      {type = "item", name = "processing-unit", amount = 20},
    } or {
      {type = "item", name = "heavy-truck", amount = 1},
  {type = "item", name = "processing-unit", amount = 50},
  {type = "item", name = "low-density-structure", amount = 50},
  {type = "item", name = "electric-engine-unit", amount = 20},
  {type = "item", name = "steel-plate", amount = 100},
}

local technology_prereq = space_age
  and {"heavy-truck", "artillery", "quantum-processor"}
  or {"heavy-truck", "artillery", "space-science-pack"}

-- data:extend
{
    type = "recipe",
    name = NAME,
    enabled = false,
    energy_required = 20,
    ingredients = truck_ingredients,
    results = {{type = "item", name = NAME, amount = 1}},
  }
{
    type = "technology",
    name = NAME,
    icon = "__heavy-trucks__/graphics/technology/v3-truck.png",
    icon_size = 256,
    effects = {{type = "unlock-recipe", recipe = NAME}, {type = "unlock-recipe", recipe = shared.missile}},
    prerequisites = technology_prereq,
    unit = {count = 2000, ingredients = space_age and space_age_packs or vanilla_packs, time = 60},
  }

Thanks for the suggestion and the code! Both are in 1.3.10, with one change:

• The V3 launcher now works without Space Age, with a base-game recipe, researched after Space science.
• With Space Age it comes earlier than before, but not as early as you suggested: after Vulcanus, Fulgora and Gleba, and before Aquilo. Its recipe takes something from each of those planets.

The reason I keep it that late is its power. It has a range of 300 and hits a 10-tile radius for 5,000 damage, so it can wipe out a whole nest from far away with no risk. Unlocking it before Gleba would make the Gleba enemies, and nests in general, trivial right when they're supposed to be a challenge. The V3 is meant as a late-game weapon: the reward for having got through the inner planets, not the tool to get through them.

Fair, I didn't really consider how powerful it is at that stage of the game without other mods that enable long-range nest clearing like Aircraft and AAI. Thanks for the update!

THIS IS WHAT V2 IS FOR