Not really. LBB2 jump drives where just large and maneuver drives small. In LBB5 it was the opposite. By dragging LBB2 maneuver drives into an LBB5 nonstarship design, you're using a cheap trick to save tonnage, is all.
The PP fuel requirements are another matter, but they are irrelevant for a 1000-ton ship such as the one discussed here. Using an LBB2 maneuver drive gave you the same performance as an LLB5 one at ~a quarter of the tonnage, simple as that.
If you allow mix-and-match, maybe. I don't.
The point of LBB5's paradigm is that things that are combat-relevant (M-Drive and the power plant to run it) are costly in MCr and tonnage, things that aren't, are less so. LBB2 is similar, but for RPG value (High Jn is useful for PCs, maneuver -- in LBB2 -- is much less so). In the size range of typical PC ships (100Td Type S, through Type R and the 600Td Type M), that 10Td/Pn
hurts. Above 1000Td, it's better than HG's fuel requirement.
But keep in mind that LBB2 constrains maneuver drive size exactly as it does jump drives and power plants. A 1000Td ship with LBB2 drives is limited to 3G and Pn-3 until TL-15! (TL-14 allows Size R-U drives, which
still only yield a rating of 3 in 1000Td.) And if it's J-3, it then can have agility no higher than 2, even without
any energy weapons, because of the computer power requirement.
And as I alluded to, the LBB5 jump drive "outsourced" the "fast-burn-fusion-reactor element" of the drive* to the "power plant in overdrive mode", bringing the increased-TL-efficiencies of HG power plants to jump drives. (In LBB2,
J-Drive + Power Plant does not vary by TL, all else about a ship being equal; in LBB5, it does vary by TL because the power plant does).
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*LBB2'77 didn't need a power plant for the jump drive (see canon XBoat), so it had to have included some kind of fusion reactor that'd burn 10% of the ship's tonnage per Jn in a ten minute combat turn(!) Drive sizes and costs were retained in the '81 version, but Pn>=Jn or Pn>=Gs, whichever was higher. Fuel use changed: jump drives could be throttled back (10% per Jn
used, not 10% per Jn the drive was
capable of -- that is, jump governors became standard; power plants still used 10Td/Jn but instead of that being "one trip, world-to-world", it was now 4 weeks worth).