Well, not a refit but a recalculation based on the 650 tons it actually is. Using this on-line ship builder, this is the initial redraft:
No Refunds, Courier Merchant
650 ton, TL 13 Civilian Design, 274.43 MCr
7 crew (Command: 1+1, Engineers: 1+2, Steward: 0+1, Medic: 0+1)
4 High/Mid passengers
__Ton._____MCr._____EP.____
| ___.__ | _39.00 | __.__ | Close Structure, partially streamlined, fuel scoops
| _52.00 | _31.20 | __.__ | hull armour #3
| __5.00 | __0.03 | __.__ | purification plant
| _20.00 | __3.25 | __.__ | bridge
| __2.00 | __9.00 | __.__ | computer model 2
| _19.50 | _78.00 | __.__ | drive jump #2
| _32.50 | _22.75 | __.__ | drive maneouver #2
| _26.00 | _78.00 | __.__ | power plant #2
| ___.__ | ___.__ | 13.00 | agility #2
| _13.00 | ___.__ | __.__ | fuel, PP endurance 4 weeks (8 weeks powered down)
| 130.00 | ___.__ | __.__ | fuel, jump range 2 parsecs
| __6.00 | __6.60 | __.__ | hard points x6 with triple turrets
| _44.00 | __5.50 | __.__ | staterooms x11
| 250.00 | ___.__ | __.__ | 250 tons cargo capacity
| __4.00 | __0.50 | __.__ | workshop
| __6.00 | __0.60 | __.__ | 1 ton low berth, emergency6 ton
| _10.00 | ___.__ | __.__ | hanger space for 10 ton place-holder
‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒
| 620.00 | 274.43 | 13.00 EP used, PP generates 13.00 EPs
277.17 MCr (first ship, includes architect fees) built in 100 weeks
219.54 MCr (20% discount in volume, TCS) built in 80 weeks
CT Ship Designer by Matt. Visit https://tca-2014-12.herokuapp.com
I need to go back over High Guard and the deckplans to see if that is about right. Still off by 30 tons but the 0-Hr deckplans are really spacious, not your typical Traveller submarine feeling. From the site and the Starfinder page (lots of great ships there! Not really great for Traveller as they aren't mostly fuel tanks, but I can live with that)
And I know, I keep saying I'll do a Mongoose version. Here is a draft of that:
Hull: 650 Closed Structure 650 32.5
286 Hull Points
Armor: 2 points Crystal [16] 1.625
Aerofins [2] 1
Manuever 2 [13] 26
Jump 2 [32.5] 48.75
Power: TL 12 Fusion [20] 20
Basic: 130
Manuever 70
Jump: 70
Emergency: 30 = 300 points
Fuel [196]
Man: 0
Power: 65
Jump: 130 Jump 2
"Fuel Compartment" 1
Fuel Scoops [1] 1
Fuel Purifying 20 tons/day [4] .2
Bridge [20] 3.25
Sensor Stations x2 [2] 1
Computer: Computer/25 TL13 10
Sensors: Military Grade {Power-2] 4.1
Staterooms: 6 [24] 3
Common Area: [15] 1.5
Full Hangar [40] 8
Airlocks: 4 [8] .8
Gaming Space [3] .018
Medical Bay [4] 2
Work Area [2] 1
Rentry/Lifeboats: 6 [3] .12
Cargo [240]
===== ====
645.5 165.863
Not quite matching, so probably need to get back to the CT designer to fine tune things. Not sure why the cost of the Mongoose is so much less - need to check my maths! Probably will dump into a spreadsheet to add things up better, and be able to save off the info. Though part of the issue is the deck plans only show 6 staterooms, so that's what I did with the manual. I'll have to adjust the passengers to 0 probably to make the 1st one fit, and readjust the cargo bay a bit.
Mongoose does its power a bit differently, but honestly that part seems more to the original spirit of Traveller: you may not have enough power to run all the things, hence the ancient tradition of dimming the lights pre-jump. Note that I've added a bit of extra power so all things can be run at once. The only thing taking extra power are the sensors.
Speaking of sensors, I know there are some quite vehement threads about having a nuclear power plant in space cannot be stealthy: basic TL 5+ sensors should pick that up. Mongoose does have sensor rules based on your equipment as well as the potential for stealth ships. While I can't say I like where Mongoose is going with Traveller (they are either re-doing stuff that has been done way too often before, or doing things that to just don't feel like Traveller), I do like the stealth rules and all that. And as Malik is the sensor/comms operator, I added 2 sensor stations as that is also what shows up in the deck plans, just behind the bridge. I like to let players roll for things.
Between the military sensors (no DM, but at least no negative DMs as per basic & civilian grade) and specialized stations that apparently have no actual game effect, the players stand a slightly better chance at sensing things. Of course, the player's skills add even more hopefully. Think I'll start using some sort of sensor rolls when I get back to my next session of exploring the League of Planets.